Per unit price or other underlying value of transaction computed pursuant to Exchange Act Rule 0-11 (set forth the amount on which the filing fee is calculated and state how it was determined):

(4)

Proposed maximum aggregate value of transaction:

(5)

Total fee paid:

o

Fee paid previously with preliminary materials.

o

Check box if any part of the fee is offset as provided by Exchange Act Rule 0-11(a)(2) and identify the filing for which the offsetting fee was paid previously. Identify the previous filing by registration statement number, or the Form or Schedule and the date of its filing.

On May 9, 2019, Anadarko Petroleum Corporation (Anadarko), Occidental Petroleum Corporation (Occidental) and Baseball Merger Sub 1, Inc., an indirect wholly owned subsidiary of Occidental, entered into a merger agreement that provides, upon the terms and subject to the conditions set forth therein, for Anadarko to become an indirect wholly owned subsidiary of Occidental (the merger). If the merger is completed, Anadarko stockholders will receive, in exchange for each share of Anadarko common stock, par value $0.10 per share (Anadarko common stock), held immediately prior to the merger, (1) $59.00 in cash and (2) 0.2934 of a share of Occidental common stock, par value $0.20 per share (Occidental common stock), subject to potential adjustments as specified in the merger agreement and as described herein. The Anadarko board of directors has unanimously approved the merger agreement, and recommends that Anadarko stockholders vote in favor of adopting the merger agreement.

Based on Occidentals closing stock price on July 8, 2019, the most recent practicable date for which such information was available, the merger consideration represented approximately $73.46 in value per share of Anadarko common stock, which represents a premium of approximately 57% over Anadarkos closing stock price on April 11, 2019, the last trading day before Anadarko announced it had entered into a merger agreement with Chevron Corporation, which merger agreement was subsequently terminated by Anadarko, and a discount of approximately 3% to Anadarkos closing stock price on May 8, 2019, the last day before the public announcement of the execution of the merger agreement with Occidental. The value of the stock portion of the merger consideration to be received in exchange for each share of Anadarko common stock will fluctuate with the market value of Occidental common stock until the transaction is complete. The common stock of each of Occidental and Anadarko is listed on the New York Stock Exchange under the symbol OXY and APC, respectively. Upon completion of the merger, former Anadarko stockholders are expected to own approximately 16% of the then outstanding Occidental common stock, based on Occidentals outstanding equity as of May 2, 2019 (without giving effect to the exercise of the warrant to be issued pursuant to the Berkshire Hathaway investment described herein).

The merger cannot be completed without approval of the proposal to adopt the merger agreement by the affirmative vote of holders of a majority of the outstanding shares of Anadarko common stock entitled to vote thereon. Because of this, Anadarko is holding a special meeting of its stockholders on August 8, 2019 to vote on the proposal necessary to complete the merger. Information about the meeting, the merger, the merger agreement, and the other business to be considered by stockholders at the special meeting is contained in this proxy statement/prospectus. The Anadarko board of directors has fixed the close of business on July 11, 2019 as the record date for the determination of Anadarko stockholders entitled to notice of, and to vote at, the special meeting. Any stockholder entitled to attend and vote at the special meeting is entitled to appoint a proxy to attend and vote on such stockholder’s behalf. Such proxy need not be a holder of Anadarko common stock. We urge you to read this proxy statement/prospectus and the annexes and documents incorporated by reference carefully. You should also carefully consider the risks that are described in the Risk Factors section beginning on page 32.

The Anadarko board of directors has unanimously determined that the merger agreement and the transactions contemplated thereby, including the merger, are advisable, fair to and in the best interests of Anadarko and the Anadarko stockholders, approved the merger agreement and the merger, and directed that the adoption of the merger agreement be submitted to a vote at a meeting of the Anadarko stockholders and unanimously recommends that Anadarko stockholders vote FOR the proposal to adopt the merger agreement.

Your vote is very important regardless of the number of shares of Anadarko common stock that you own.

Whether or not you plan to attend the special meeting, please submit your proxy as soon as possible to make sure that your shares are represented at the meeting. If your shares are held in the name of a broker, bank or other nominee, please follow the instructions on the voting instruction card furnished by the broker, bank or other nominee. You must provide voting instructions by filling out the voting instruction card in order for your shares to be voted.

Thank you for your continued support, interest and investment in Anadarko.

Very truly yours,

Al WalkerChairman of the Board andChief Executive Officer

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of the merger or the other transactions described in this proxy statement/prospectus or the securities to be issued in connection with the merger or determined if this proxy statement/prospectus is accurate or complete. Any representation to the contrary is a criminal offense.

This proxy statement/prospectus is dated July 11, 2019, and is first being mailed to stockholders of Anadarko on or about July 11, 2019.

We are pleased to invite you to attend the special meeting of stockholders of Anadarko Petroleum Corporation, a Delaware corporation (Anadarko), which will be held at The Westin at The Woodlands, 2 Waterway Square Place, The Woodlands, Texas, 77380, on August 8, 2019, at 8:00 a.m., local time, for the following purposes:

•

to vote on a proposal to adopt the Agreement and Plan of Merger, dated as of May 9, 2019, by and among Occidental Petroleum Corporation (Occidental), a Delaware corporation, Baseball Merger Sub, 1 Inc., an indirect wholly owned subsidiary of Occidental (Merger Subsidiary), and Anadarko (as it may be amended from time to time, the merger agreement), which is further described in the sections titled The Merger and The Merger Agreement, beginning on pages 41 and 101, respectively, and a copy of which is attached as Annex A to the proxy statement/prospectus of which this notice is a part (the merger proposal); and

•

to vote on an advisory (non-binding) proposal to approve the compensation that may be paid or become payable to Anadarko’s named executive officers that is based on or otherwise related to the merger (the merger-related compensation proposal).

Anadarko will transact no other business at the special meeting except such business as may properly be brought before the special meeting or any adjournment or postponement thereof by or at the direction of the Anadarko board of directors. Please refer to the proxy statement/prospectus of which this notice is a part for further information with respect to the business to be transacted at the special meeting.

The Anadarko board of directors has fixed the close of business on July 11, 2019 as the record date for the special meeting. Only Anadarko stockholders of record at the record date are entitled to receive notice of, and to vote at, the special meeting or any adjournment or postponement thereof. A complete list of stockholders entitled to vote at the special meeting will be available for viewing by any Anadarko stockholder during ordinary business hours for a period of ten days before the meeting, for purposes pertaining to the special meeting, at Anadarkos offices at 1201 Lake Robbins Drive, The Woodlands, Texas 77380. The eligible Anadarko stockholder list will also be available at the special meeting for examination by any stockholder of record present at such meeting.

Completion of the merger is conditioned on adoption of the merger agreement by the Anadarko stockholders, which requires the affirmative vote of holders of a majority of the outstanding shares of Anadarko common stock entitled to vote thereon.

The Anadarko board of directors has unanimously determined that the merger agreement and the transactions contemplated thereby, including the merger, are advisable, fair to and in the best interests of Anadarko and the Anadarko stockholders, approved the merger agreement and the merger, and directed that the adoption of the merger agreement be submitted to a vote at a meeting of the holders of Anadarko common stock and unanimously recommends that Anadarko stockholders vote FOR the merger proposal and FOR the merger-related compensation proposal.

Your vote is very important regardless of the number of shares of Anadarko common stock that you own. Whether or not you expect to attend the special meeting in person, we urge you to submit your vote in advance of the meeting. If your shares are held in the name of a broker, bank or other nominee, please vote by following the instructions on the voting instruction card furnished by the broker, bank or other nominee. If you hold your shares in your own name, submit a proxy to vote your shares as promptly as possible by

(i) visiting the internet site listed on the proxy card, (ii) calling the toll-free number listed on the proxy card or (iii) submitting your proxy card by mail by using the provided self-addressed, stamped envelope. Submitting a proxy will not prevent you from voting in person, but it will help to secure a quorum and avoid added solicitation costs. Any eligible holder of Anadarko common stock who is present at the special meeting may vote in person, thereby revoking any previous proxy. In addition, a proxy may also be revoked in writing before the special meeting in the manner described in the proxy statement/prospectus of which this notice is a part.

The proxy statement/prospectus of which this notice is a part provides a detailed description of the merger and the merger agreement and the other matters to be considered at the special meeting. We urge you to carefully read this proxy statement/prospectus, including any documents incorporated by reference herein, and the annexes in their entirety. In particular, we urge you to carefully read the section entitled Risk Factors beginning on page 32. If you have any questions concerning the merger or this proxy statement/prospectus, would like additional copies or need help voting your shares of Anadarko common stock, please contact either of Anadarko’s proxy solicitors:

This proxy statement/prospectus incorporates by reference important business and financial information about Occidental and Anadarko from other documents that are not included in or delivered with this proxy statement/prospectus. For a listing of the documents incorporated by reference into this proxy statement/prospectus, see Where You Can Find More Information beginning on page 167.

You can obtain any of the documents incorporated by reference into this proxy statement/prospectus without charge by requesting them in writing or by telephone as follows:

To receive timely delivery of the documents in advance of the special meeting of Anadarko stockholders, you should make your request no later than August 1, 2019, which is five business days before the meeting.

You may also obtain any of the documents incorporated by reference into this proxy statement/prospectus without charge through the Securities and Exchange Commission (the SEC) website at www.sec.gov. In addition, you may obtain copies of documents filed by Occidental with the SEC by accessing Occidentals website at www.oxy.com under the tab Investors and then under the heading SEC Filings. You may also obtain copies of documents filed by Anadarko with the SEC by accessing Anadarkos website at www.anadarko.com under the tab Investors and then under the heading Financial Information.

We are not incorporating the contents of the websites of the SEC, Occidental, Anadarko or any other entity into this proxy statement/prospectus. We are providing the information about how you can obtain certain documents that are incorporated by reference into this proxy statement/prospectus at these websites only for your convenience.

This document, which forms part of a registration statement on Form S-4 filed with the SEC by Occidental (File No. 333-232001), constitutes a prospectus of Occidental under Section 5 of the Securities Act of 1933, as amended (the Securities Act), with respect to the shares of common stock, par value $0.20 per share, of Occidental (Occidental common stock) to be issued to Anadarko stockholders pursuant to the merger agreement. This document also constitutes a proxy statement of Anadarko under Section 14(a) of the Securities Exchange Act of 1934, as amended (the Exchange Act). It also constitutes a notice of meeting with respect to the special meeting, at which Anadarko stockholders will be asked to consider and vote on the adoption of the merger agreement.

Occidental has supplied all information contained in, and incorporated by reference into, this proxy statement/prospectus relating to Occidental and Merger Subsidiary, and Anadarko has supplied all such information relating to Anadarko.

You should rely only on the information contained in, and incorporated by reference into, this proxy statement/prospectus. Occidental and Anadarko have not authorized anyone to provide you with information other than the information that is contained in, or incorporated by reference into, this proxy statement/prospectus. Occidental and Anadarko take no responsibility for, and can provide no assurances as to the reliability of, any other information that others may give you. This proxy statement/prospectus is dated July 11, 2019, and you should not assume that the information contained in this proxy statement/prospectus is accurate as of any date other than such date. Further, you should not assume that the information incorporated by reference into this proxy statement/prospectus is accurate as of any date other than the date of the incorporated document. Neither the mailing of this proxy statement/prospectus to Anadarko stockholders nor the issuance by Occidental of shares of Occidental common stock pursuant to the merger agreement will create any implication to the contrary.

The following questions and answers briefly address some commonly asked questions about the merger and the special meeting of Anadarko stockholders (the special meeting). They may not include all the information that is important to stockholders of Anadarko. Anadarko stockholders should carefully read this entire proxy statement/prospectus, including the annexes and the other documents referred to or incorporated by reference in this proxy statement/prospectus. See Where You Can Find More Information beginning on page 167 of this proxy statement/prospectus.

Q: What is the merger?

Occidental Petroleum Corporation (Occidental), Baseball Merger Sub 1, Inc., an indirect wholly owned subsidiary of Occidental (Merger Subsidiary), and Anadarko Petroleum Corporation (Anadarko) have entered into an Agreement and Plan of Merger, dated May 9, 2019 (as it may be amended from time to time, the merger agreement). A copy of the merger agreement is attached as Annex A to this proxy statement/prospectus. The merger agreement contains the terms and conditions of the proposed acquisition of Anadarko by Occidental. Under the merger agreement, subject to satisfaction (or, to the extent permitted by law and in accordance with the merger agreement, waiver) of the conditions to the merger set forth in the merger agreement and described in this proxy statement/prospectus, Merger Subsidiary will merge with and into Anadarko, with Anadarko continuing as the surviving corporation and an indirect wholly owned subsidiary of Occidental (the merger or the transaction).

As a result of the merger, Anadarko will no longer be a publicly held company. Following the merger, Anadarko common stock will be delisted from the New York Stock Exchange (the NYSE) and will be deregistered under the Exchange Act, after which Anadarko will no longer be required under SEC rules and regulations to file periodic reports with the SEC in respect of Anadarko common stock.

Q: Why am I receiving these materials?

Occidental and Anadarko are sending these materials to Anadarko stockholders to help them decide how to vote their shares of Anadarko common stock with respect to the merger and other matters to be considered at the special meeting.

The merger cannot be completed unless Anadarko stockholders adopt the merger agreement with the affirmative vote of the holders of a majority of the outstanding shares of Anadarko common stock entitled to vote thereon. Anadarko is holding a special meeting of its stockholders to vote on the proposals necessary to complete the merger. Information about this special meeting, the merger and the other business to be considered by stockholders at the special meeting is contained in this proxy statement/prospectus.

This proxy statement/prospectus constitutes both a proxy statement of Anadarko and a prospectus of Occidental. It is a proxy statement because the board of directors of Anadarko (the Anadarko Board) is soliciting proxies from its stockholders. It is a prospectus because Occidental will issue shares of its common stock in exchange for outstanding shares of Anadarko common stock in the merger.

Q: What will Anadarko stockholders receive in the merger?

In the merger, Anadarko stockholders will receive $59.00 in cash, without interest (as such amount of cash may potentially be adjusted pursuant to the merger agreement as described below, the per share cash consideration), and 0.2934 (as such amount may potentially be adjusted pursuant to the merger agreement as described below, the exchange ratio) of a validly issued, fully paid and non-assessable share of Occidental common stock (such cash consideration and stock consideration together, as they may potentially be adjusted pursuant to the merger agreement as described below, the merger consideration) for each share of Anadarko common stock (other than (i) shares held by Occidental, Anadarko, Merger Subsidiary or any of their respective direct or indirect wholly owned subsidiaries (cancelled shares), (ii) certain shares of Anadarko common stock subject to stock-based awards that will be treated in the manner described under the heading The Merger—Treatment of Anadarko Stock Options and Other Stock-Based Awards and (iii) shares of Anadarko common stock with respect to which appraisal rights are properly demanded and not withdrawn (dissenting shares) under the General Corporation Law of the State of Delaware (the DGCL)).

If the merger would otherwise result in the issuance of shares of Occidental common stock (including shares that would be deliverable pursuant to converted stock-based awards pursuant to the merger agreement) in excess of 19.99% of the outstanding shares of Occidental common stock immediately prior to the closing of the merger (the share cap), (i) the exchange ratio will be reduced by the smallest number (rounded up to the nearest 0.0001) that causes the total number of shares of Occidental common stock (including shares that would be deliverable pursuant to converted stock-based awards pursuant to the merger agreement) issuable in the merger to not exceed the share cap (the exchange ratio reduction number) and (ii) the per share cash consideration will be increased by an amount in cash equal to (x) the exchange ratio reduction number multiplied by (y) the closing price per share of Occidental common stock on the NYSE on the last trading day immediately preceding the closing date of the merger (the Parent Closing Price).

The exchange ratio is otherwise fixed and will not be adjusted to reflect changes in the stock price of either company before the merger is complete. No fractional shares of Occidental common stock will be issued in connection with the merger. Each holder of Anadarko common stock that otherwise would have been entitled to receive a fractional share of Occidental common stock immediately prior to the effective time of the merger will receive an amount in cash, without interest, rounded to the nearest cent, in lieu of such fractional share. The value of such cash payment will be calculated by the exchange agent and will represent the holder’s proportionate interest in a trust of proceeds established from the open-market sale of that number of shares of Occidental common stock equal to the excess of (x) the aggregate number of shares of Occidental common stock delivered to the exchange agent by Occidental pursuant to the terms of the merger agreement over (y) the aggregate number of whole shares of Occidental common stock distributed to the holders of certificates or book-entry shares previously representing shares of Anadarko common stock pursuant to the merger agreement. Occidental stockholders will continue to own their existing shares of Occidental common stock, the form of which will not be changed by the transaction. For more details on the merger consideration, see The Merger Agreement—Merger Consideration beginning on page 102.

The merger will be treated as a taxable transaction for U.S. federal income tax purposes. Therefore, a U.S. holder (as defined below in the section entitled The Merger—Material U.S. Federal Income Tax Consequences—General) generally will recognize capital gain or loss equal to the difference between (1) the sum of the cash and the fair market value of any shares of Occidental common stock received by such U.S. holder in the merger and (2) the U.S. holder’s adjusted tax basis in its Anadarko common stock. Except in certain circumstances described in The Merger—Material U.S. Federal Income Tax Consequences—The Merger, a Non-U.S. holder (as defined below in the section entitled The Merger—Material U.S. Federal Income Tax Consequences—General) generally will not be subject to U.S. federal income or withholding tax on any gain recognized on the exchange of Anadarko common stock for any shares of Occidental common stock and cash in the merger. You are strongly urged to consult with a tax advisor to determine the particular U.S. federal, state or local or foreign income or other tax consequences of the merger to you. For additional information, see The Merger—Material U.S. Federal Income Tax Consequences beginning on page 96.

Q: What equity stake will Anadarko stockholders hold in Occidental immediately following the merger?

Upon the completion of the merger, based on the exchange ratio, the estimated number of shares of Occidental common stock issuable as the stock portion of the merger consideration is approximately 146.3 million shares, which will result in former Anadarko stockholders holding approximately 16% of the outstanding fully diluted Occidental common stock based on the number of outstanding shares of common stock and outstanding stock-based awards of Occidental and Anadarko as of May 2, 2019, the most recent practicable date for which such information was available.

For more details on the merger consideration and the treatment of Anadarko stock options and stock-based awards, see The Merger Agreement—Merger Consideration beginning on page 102 and The Merger Agreement—Merger Consideration—Treatment of Anadarko Stock Options and Other Stock-Based Awards beginning on page 104, respectively.

Occidental and Anadarko are working to complete the merger as soon as practicable and currently expect that the transaction will be completed in the second half of 2019. Neither Occidental nor Anadarko can predict, however, the actual date on which the transaction will be completed because it is subject to conditions beyond each company’s control. See The Merger Agreement—Conditions to Completion of the Merger beginning on page 120.

Q: Is Occidentals obligation to complete the merger subject to Occidental receiving financing?

No. Occidental’s obligations under the merger agreement are not subject to any condition regarding its ability to finance, or obtain financing for, the merger. For more information regarding financing of the merger, see The Merger—Financing of the Merger and Treatment of Existing Debt beginning on page 89.

Q: What happens if the merger is not completed?

If the merger agreement is not adopted by Anadarko stockholders or if the merger is not completed for any other reason, Anadarko stockholders will not receive any consideration for their shares of Anadarko common stock. Instead, Anadarko will remain an independent public company, Anadarko common stock will continue to be listed and traded on the NYSE and registered under the Exchange Act and Anadarko will continue to file periodic reports with the SEC. Under specific circumstances, Anadarko or Occidental may be required to pay the other party a termination fee of $1 billion. See The Merger Agreement—Termination of the Merger Agreement beginning on page 120.

Q: Will the shares of Occidental common stock I acquire in the merger receive a dividend?

After the closing of the merger, as a holder of Occidental common stock, you will receive the same dividends on shares of Occidental common stock that all other holders of shares of Occidental common stock will receive with any dividend record date that occurs after the closing of the merger.

Q: Will I continue to receive dividends in respect of my shares of Anadarko common stock?

Prior to the closing of the merger, Anadarko and Occidental will coordinate regarding the declaration and payment of dividends in respect of their common stock and the record dates and payment dates relating thereto, so as to ensure that you do not receive two dividends, or fail to receive one dividend, in any quarter with respect to your shares of Anadarko common stock and the Occidental common stock that you receive in exchange therefor in the merger.

After the closing of the merger, former Anadarko stockholders who hold Anadarko share certificates will not be entitled to be paid dividends otherwise payable on the shares of Occidental common stock into which their shares of Anadarko common stock are exchangeable until they surrender their Anadarko share certificates according to the instructions provided to them. Dividends will be accrued for these stockholders and they will receive the accrued dividends when they surrender their Anadarko share certificates.

After the closing of the merger, all Occidental dividends will remain subject to approval by Occidentals board of directors (the Occidental Board).

Q: What am I being asked to vote on, and why is this approval necessary?

Anadarko stockholders are being asked to vote on the following proposals:

1.

a proposal to adopt the merger agreement, a copy of which is attached as Annex A to this proxy statement/prospectus, which is further described in the sections titled The Merger and The Merger Agreement, beginning on pages 41 and 101, respectively (the merger proposal); and

2.

an advisory (non-binding) proposal to approve the compensation that may be paid or become payable to Anadarko’s named executive officers that is based on or otherwise related to the merger (the merger-related compensation proposal).

Approval of the merger proposal by the affirmative vote of holders of a majority of the outstanding shares of Anadarko common stock entitled to vote thereon is required for completion of the merger.

Q: What vote is required to approve each proposal at the special meeting?

The merger proposal: The affirmative vote of holders of a majority of the outstanding shares of Anadarko common stock entitled to vote thereon is required to approve the merger proposal (the Anadarko stockholder approval).

The merger-related compensation proposal: The affirmative vote of holders of a majority of the outstanding shares of Anadarko common stock present in person or represented by proxy at the special meeting and entitled to vote thereon is required to approve the merger-related compensation proposal. Because the vote on the merger-related compensation proposal is advisory only, it will not be binding on either Anadarko or Occidental. Accordingly, if the merger agreement is adopted and the merger is completed, the merger-related compensation will be payable to Anadarkos named executive officers, subject only to the conditions applicable thereto, regardless of the outcome of the non-binding, advisory vote of Anadarkos stockholders.

Q: What happens if the non-binding, advisory merger-related compensation proposal is not approved?

Because the vote on the merger-related compensation proposal is advisory only, it will not be binding on either Anadarko or Occidental. Accordingly, if the merger proposal is approved and the merger is completed, the merger-related compensation will be payable to Anadarkos named executive officers, subject only to the conditions applicable thereto, regardless of the outcome of the approval of the merger-related compensation proposal.

Q: What constitutes a quorum?

The presence at the special meeting, in person or by proxy, of the holders of a majority of the outstanding shares of Anadarko common stock entitled to vote at the special meeting will constitute a quorum for the transaction of business at the special meeting. Abstentions will count as votes present and entitled to vote for the purpose of determining the presence of a quorum for the transaction of business at the special meeting. Brokers, banks or other nominees that hold shares for beneficial owners do not have discretionary authority to vote the shares as to any matter at the meeting without receiving voting instructions from the beneficial owners. Such shares will be considered to be broker non-votes and will not be counted as present for quorum purposes.

A quorum is necessary to transact business at the special meeting. The Anadarko by-laws and the DGCL provide that if a quorum fails to attend any meeting, the chairman of the meeting or the holders of a majority of the votes entitled to be cast by the stockholders who are present in person or by proxy may adjourn the meeting from time to time, without notice other than by announcement at the meeting, to another date, place, if any, and time until a quorum is present, unless the adjournment is for more than 30 days or, after adjournment, a new record date is fixed for the adjourned meeting.

After carefully reading and considering the information contained in, and incorporated by reference into, this proxy statement/prospectus, please vote your shares as soon as possible so that your shares will be represented at the special meeting. Please follow the instructions set forth on the proxy card or on the voting instruction form provided by the record holder if your shares are held in the name of your broker, bank or other nominee.

Please do not submit your Anadarko stock certificates at this time. After the merger is completed, you will receive instructions for surrendering your Anadarko stock certificates in exchange for shares of Occidental common stock from the exchange agent.

Please carefully consider the information contained in, and incorporated by reference into, this proxy statement/prospectus. Whether or not you plan to attend the special meeting, Anadarko encourages you to submit your proxy to vote via the internet, by telephone or by mail so that your shares will be voted in accordance with your wishes even if you later decide not to attend the special meeting.

If you are a stockholder of record, you may also cast your vote in person at the special meeting. If you decide to attend the special meeting and vote in person, your vote by ballot will revoke any proxy previously submitted.

If your shares are held in street name, through a broker, bank or other nominee, that institution will send you separate instructions describing the procedure for voting your shares. Street name stockholders who wish to vote at the meeting will need to obtain a legal proxy form from their broker, bank or other nominee.

Q: When and where is the special meeting of stockholders? What must I bring to attend the special meeting?

The special meeting of Anadarko stockholders will be held at The Westin at The Woodlands, 2 Waterway Square Place, The Woodlands, Texas, 77380 at 8:00 a.m., local time, on August 8, 2019. Subject to space availability, all Anadarko stockholders as of the record date, or their duly appointed proxies, may attend the meeting. Since seating is limited, admission to the meeting will be on a first-come, first-served basis. Registration and seating will begin at 7:30 a.m., local time.

If you wish to attend the special meeting, you must bring valid photo identification, such as a drivers license or passport. If you hold your shares of Anadarko common stock in street name, such as through a broker, bank or other nominee, you must also bring proof of ownership such as the voting instruction card from your broker or other nominee or an account statement showing your ownership as of the record date. In addition, no cameras, recording equipment, electronic devices, large bags, briefcases or packages will be permitted in the special meeting.

Q: What is the difference between holding shares as a stockholder of record and as a beneficial owner?

If your shares of Anadarko common stock are registered directly in your name with the transfer agent of Anadarko, Computershare, you are considered the stockholder of record with respect to those shares. As the stockholder of record, you have the right to vote or to grant a proxy for your vote directly to Anadarko or to a third party to vote at the special meeting.

If your shares are held by a broker, bank or other nominee, you are considered the beneficial owner of shares held in street name, and your broker, bank or other nominee is considered the stockholder of record with respect to those shares. Your broker, bank or other nominee will send you, as the beneficial owner, voting instructions for you to use in directing the broker, bank or other nominee in how to vote your shares. You should follow the instructions provided by them to vote your shares. You are invited to attend the special meeting; however, you may not vote these shares in person at the special meeting unless you obtain a legal proxy from your broker, bank or other nominee that holds your shares, giving you the right to vote the shares at the special meeting.

Q: If my shares are held in street name by a broker, bank or other nominee, will my broker, bank or other nominee vote my shares for me?

If your shares are held in street name in a stock brokerage account or by a broker, bank or other nominee, you must provide the record holder of your shares with instructions on how to vote your shares. Please follow the voting instructions provided by your broker, bank or other nominee. Please note that you may not vote shares held in street name by returning a proxy card directly to Anadarko or by voting in person at the special meeting unless you provide a legal proxy, which you must obtain from your broker, bank or other nominee. Your broker, bank or other nominee is obligated to provide you with a voting instruction card for you to use.

The NYSE permits brokers to vote their customers stock held in street name on routine matters when the brokers have not received voting instructions from their customers. The NYSE does not, however, allow brokers to vote their customers stock held in street name on non-routine matters unless they have received voting instructions from their customers. In such cases, the uninstructed shares for which the broker is unable to vote are called broker non-votes. The merger proposal and the merger-related compensation proposal are non-routine matters on which brokers are not allowed to vote unless they have received voting instructions from their customers.

If you are an Anadarko stockholder and you do not instruct your broker, bank or other nominee on how to vote your shares:

•

your broker, bank or other nominee may not vote your shares on the merger proposal, which broker non-votes, if any, will have the same effect as a vote cast AGAINST this proposal; and

•

your broker, bank or other nominee may not vote your shares on the merger-related compensation proposal, which broker non-votes, if any, will have no effect on the vote for this proposal (assuming a quorum is present).

Q: What if I fail to vote or abstain?

For purposes of the special meeting, an abstention occurs when a stockholder attends the special meeting in person and does not vote or returns a proxy with an abstain instruction.

Merger proposal: An abstention or failure to vote will have the same effect as a vote cast AGAINST the merger proposal.

Merger-related compensation proposal: An abstention will have the same effect as a vote cast AGAINST the merger-related compensation proposal. If an Anadarko stockholder is not present in person at the special meeting and does not respond by proxy, it will have no effect on the vote for the merger-related compensation proposal (assuming a quorum is present).

Q: What will happen if I return my proxy or voting instruction card without indicating how to vote?

If you sign and return your proxy or voting instruction card without indicating how to vote on any particular proposal, the Anadarko common stock represented by your proxy will be voted as recommended by the Anadarko Board with respect to that proposal.

Q: May I change or revoke my vote after I have delivered my proxy or voting instruction card?

Yes. If you are a record holder, you may change or revoke your vote before your proxy is voted at the special meeting as described herein. You may do this in one of four ways:

(1)

submitting a proxy at a later time by internet or telephone until 11:59 p.m. Eastern Time on August 7, 2019;

(2)

voting in person at the special meeting;

(3)

delivering, before 6:00 p.m. Eastern Time on August 7, 2019, to Anadarko’s Corporate Secretary at Anadarko’s executive offices at 1201 Lake Robbins Drive, The Woodlands, Texas 77380, a proxy with a later date or a written revocation of your most recent proxy; or

(4)

giving written revocation to the inspector of election at the special meeting.

If you are a street name stockholder (for example, if your shares are held in the name of a broker, bank or other holder of record) and you vote by proxy, you may later revoke your proxy by informing the holder of record in accordance with that entitys procedures.

Q: What are the material U.S. federal income tax consequences of the merger?

The merger will be treated as a taxable transaction for U.S. federal income tax purposes. Therefore, a U.S. holder (as defined below in the section entitled The Merger—Material U.S. Federal Income Tax Consequences—General) generally will recognize capital gain or loss equal to the difference between (1) the sum of the cash and the fair market value of any shares of Occidental common stock received by such U.S. holder in the merger and (2) the U.S. holders adjusted tax basis in its Anadarko common stock.

Except in certain circumstances described in The Merger—Material U.S. Federal Income Tax Consequences—The Merger, a Non-U.S. holder (as defined below in the section entitled The Merger—Material U.S. Federal Income Tax Consequences—General) generally will not be subject to U.S. federal income or withholding tax on any gain recognized on the exchange of Anadarko common stock for any shares of Occidental common stock and cash in the merger.

In certain circumstances, Anadarko stockholders who expect to own an equal or greater percentage interest in Occidental following the merger than their percentage interest in Anadarko prior to the merger, taking into account the application of certain constructive ownership rules, may have tax consequences that differ materially from those described above as a result of the application of Section 304 of the Internal Revenue Code of 1986, as amended (the Code). All references in this proxy statement/prospectus to Section 304 are to Section 304 of the Code. As described further below under The Merger—Material U.S. Federal Income Tax Consequences—The Merger—Special Consequences of the Merger to Holders of Anadarko Common Stock That Also Own Occidental Common Stock, such stockholders may be required to include the entire amount of the consideration received as dividend income. Non-U.S. holders may be subject to U.S. federal income and withholding tax on such dividend income. In addition, withholding agents may withhold on consideration payable to all Non-U.S. holders because they may not be able to determine whether any particular Non-U.S. holder is subject to withholding as a result of these rules. Any such stockholders who expect to own an equal or greater percentage interest in Occidental following the merger than their percentage interest in Anadarko prior to the merger and all Non-U.S. holders should consult their own tax advisors regarding the application of Section 304 to the merger.

Please refer to The Merger—Material U.S. Federal Income Tax Consequences—The Merger contained in this proxy statement/prospectus for a description of the material U.S. federal income tax consequences of the merger. Determining the actual tax consequences of the merger to you may be complex and will depend on your specific situation. You are urged to consult your tax advisor for a full understanding of the tax consequences of the merger to you.

Q: Am I entitled to exercise appraisal rights in connection with the merger instead of receiving the merger consideration for my shares of Anadarko common stock?

Under Delaware law, if the merger is completed, holders of Anadarko common stock who do not vote in favor of the adoption of the merger agreement and otherwise comply with the requirements and procedures of Section 262 of the DGCL may exercise their rights of appraisal, which generally entitle stockholders to receive a cash payment equal to the fair value of their Anadarko common stock exclusive of any element of value arising from the accomplishment or expectation of the merger, as determined by the Delaware Court of Chancery. The fair value could be higher or lower than, or the same as, the merger consideration. For a more detailed description of the appraisal rights available to Anadarko stockholders and the procedures required to exercise appraisal rights, see The Merger—Appraisal Rights beginning on page 92. A copy of the full text of Section 262 of the DGCL is attached as Annex D to this proxy statement/prospectus.

Q: What will happen to Anadarko stock options and other stock-based awards?

Upon completion of the merger:

•

Each outstanding option to purchase shares of Anadarko common stock, whether or not vested (an Anadarko stock option), will be cancelled and converted into the right to receive a cash amount equal to the product of:

•

the excess, if any, of (i) the sum, rounded to the nearest whole cent, of (x) the product of the exchange ratio and the Parent Closing Price and (y) the per share cash consideration (the amount in this clause (i), the Option Consideration) over (ii) the per share exercise price of such Anadarko stock option; and

•

the aggregate number of shares of Anadarko common stock subject to such Anadarko stock option.

Each Anadarko stock option with an exercise price equal to or greater than the Option Consideration will be cancelled and terminated, without any payment in respect thereof.

•

Each outstanding award of restricted stock units that corresponds to shares of Anadarko common stock (an Anadarko RSU award) will convert into a restricted stock and cash unit award of Occidental (an Occidental restricted stock/cash unit award) with respect to both:

•

the number (rounded to the nearest whole number) of shares of Occidental common stock determined by multiplying (i) the number of shares of Anadarko common stock subject to such Anadarko RSU award by (ii) the exchange ratio, and

the U.S. dollar amount (rounded to the nearest whole cent) determined by multiplying (i) the number of shares of Anadarko common stock subject to such Anadarko RSU award by (ii) the per share cash consideration.

The Occidental restricted stock/cash unit award will otherwise continue on the same terms and conditions as were applicable under such Anadarko RSU award, including any provisions for acceleration of vesting. Such terms and conditions include double-trigger protection of the converted award, meaning that upon certain qualifying terminations of employment during the applicable protection period following the closing of the merger, the award will immediately vest and become unrestricted as of such termination.

the number (rounded to the nearest whole number) of shares of Occidental common stock determined by multiplying (i) the number of shares of Anadarko common stock subject to such Anadarko RS award by (ii) the exchange ratio, and

•

the U.S. dollar amount (rounded to the nearest whole cent) determined by multiplying (i) the number of shares of Anadarko common stock subject to such Anadarko RS award by (ii) the per share cash consideration.

The Occidental restricted stock/cash award will otherwise continue on the same terms and conditions as were applicable under such Anadarko RS award, including any provisions for acceleration of vesting. Such terms and conditions include double-trigger protection of the converted award, meaning that upon certain qualifying terminations of employment during the applicable protection period following the closing of the merger, the award will immediately vest and become unrestricted as of such termination.

•

Each outstanding award of performance units (an Anadarko PU award) will immediately vest and will be cancelled and converted into the right to receive a cash amount equal to the product of (i) 200% of the target number of shares of Anadarko common stock subject to such Anadarko PU award multiplied by (ii) $76.00, less applicable tax withholdings. This amount will be payable on the earliest date that would not result in the imposition of any tax under Section 409A of the Code.

•

Each outstanding deferred share award (an Anadarko deferred share award) will be cancelled and converted into the right to receive the merger consideration in respect of each share of Anadarko common stock subject to such Anadarko deferred share award. This amount will be payable within five business days following the completion of the merger or, if later, the earliest date that would not result in the imposition of tax under Section 409A of the Code.

Q: What happens if I sell my shares of Anadarko common stock after the record date but before the special meeting?

The record date for the special meeting (the close of business on July 11, 2019) is earlier than the date of the special meeting and earlier than the date that the merger is expected to be completed. If you sell or otherwise transfer your shares of Anadarko common stock after the record date but before the date of the special meeting, you will retain your right to vote at the special meeting. However, you will not have the right to receive the merger consideration to be received by Anadarko stockholders in the merger or to demand appraisal rights. In order to receive the merger consideration or demand appraisal rights, you must hold your shares through completion of the merger.

Q: Are there any risks that I should consider in deciding whether to vote in favor of the merger proposal?

Yes. You should read and carefully consider the risk factors set forth in the section entitled Risk Factors beginning on page 32. You also should read and carefully consider the risk factors of Occidental and Anadarko contained in the documents that are incorporated by reference into this proxy statement/prospectus.

Q: What should I do if I receive more than one set of voting materials?

If you hold shares of Anadarko common stock in street name and also directly as a record holder or otherwise or if you hold shares of Anadarko common stock in more than one brokerage account, you may receive more than one set of voting materials relating to the special meeting. Please complete, sign, date and return each proxy card (or cast your vote by telephone or internet as provided on your proxy card) or otherwise follow the voting instructions provided in this proxy statement/prospectus in order to ensure that all of your shares of Anadarko common stock are voted. If you hold your shares in street name through a broker, bank or other nominee, you should follow the procedures provided by your broker, bank or other nominee to vote your shares.

Q: Who will tabulate and certify the vote?

Broadridge Financial Solutions, Inc. (Broadridge), an independent third party, will tabulate and certify the vote, and will have a representative to act as the independent inspector of election for the special meeting.

Q: Where can I find the voting results of the special meeting?

The preliminary voting results will be announced at the special meeting. In addition, within four business days following certification of the final voting results, Anadarko intends to file the final voting results with the SEC on a Current Report on Form 8-K.

Q: Whom should I contact if I have any questions about the proxy materials or voting?

If you have any questions about the proxy materials, or if you need assistance submitting your proxy or voting your shares or need additional copies of this proxy statement/prospectus or the enclosed proxy card, you should contact the proxy solicitation agents for Anadarko, at:

This summary highlights selected information contained in this proxy statement/prospectus and does not contain all the information that may be important to you. Occidental and Anadarko urge you to read carefully this proxy statement/prospectus in its entirety, including the annexes. Additional important information, which Occidental and Anadarko also urge you to read, is contained in the documents incorporated by reference into this proxy statement/prospectus. See Where You Can Find More Information beginning on page167. Unless stated otherwise, all references in this proxy statement/prospectus to Occidental are to Occidental Petroleum Corporation, all references to Anadarko are to Anadarko Petroleum Corporation and all references to the merger agreement are to the Agreement and Plan of Merger, dated as of May 9, 2019, by and among Occidental Petroleum Corporation, Baseball Merger Sub 1, Inc. and Anadarko Petroleum Corporation, a copy of which is attached as Annex A to this proxy statement/prospectus.

Information about the Companies

Occidental

Occidental is an international oil and gas exploration and production company with operations in the United States, Middle East and Latin America. Headquartered in Houston, Occidental is one of the largest U.S. oil and gas companies, based on equity market capitalization. Occidentals principal businesses consist of three segments as follows:

Oil and Gas—This segment explores for, develops and produces oil and condensate, natural gas liquids (NGLs) and natural gas. Occidentals oil and gas assets are located in some of the worlds highest-margin basins and are characterized by an advantaged mix of short- and long-cycle, high-return development opportunities. In the United States, Occidental holds a leading position in the Permian Basin. Other core operations are in the Middle East (Oman, United Arab Emirates (UAE) and Qatar) and Latin America (Colombia).

Chemical (OxyChem)—This segment primarily manufactures and markets basic chemicals and vinyls. OxyChem is a leading North American manufacturer of PVC resins, chlorine and caustic soda − key building blocks of products such as pharmaceuticals, water treatment chemicals and durable, long-life plastics. OxyChem has manufacturing facilities in the United States, Canada and Latin America.

Midstream and Marketing—This segment purchases, markets, gathers, processes, transports and stores oil, condensate, NGL, natural gas, carbon dioxide and power. It also trades around its assets, including transportation and storage capacity, and invests in entities that conduct similar activities. Also within the midstream and marketing segment is Oxy Low Carbon Ventures (“OLCV”). OLCV seeks to capitalize on Occidentals enhanced oil recovery leadership by developing carbon capture, utilization and storage projects that source anthropogenic carbon dioxide and promote innovative technologies that drive cost efficiencies and grow Occidentals business while reducing emissions.

Occidental is incorporated in Delaware. Its principal executive offices are located at 5 Greenway Plaza, Suite 110, Houston, Texas 77046 and its telephone number is (713) 215-7000. Occidental’s website address is www.oxy.com. Information contained on Occidental’s website does not constitute part of this proxy statement/prospectus. Occidental’s common stock is publicly traded on the NYSE, under the ticker symbol OXY. Additional information about Occidental is included in documents incorporated by reference in this proxy statement/prospectus. See Where You Can Find More Information beginning on page 167.

Anadarko

Anadarko is among the worlds largest independent exploration and production companies, with approximately 1.5 billion barrels of oil equivalent (BOE) of proved reserves at December 31, 2018. Anadarkos asset portfolio combines cash-generating conventional oil developments in the Gulf of Mexico, Algeria and Ghana with a large inventory of significant and proven high-growth unconventional resources in the U.S. onshore. Anadarkos U.S. onshore assets include the Delaware and Denver-Julesburg (DJ) basins and an emerging play in the Powder River basin. Anadarkos asset portfolio also includes a world-class natural-gas discovery in Mozambique as well as other worldwide exploration and development opportunities.

On February 28, 2019, Anadarko completed the previously announced contribution and sale of substantially all of its midstream assets to Western Midstream Partners, LP, a publicly traded limited partnership and

consolidated subsidiary of Anadarko and formerly known as Western Gas Equity Partners, LP. Due to this contribution and sale, as of the filing on May 8, 2019 of its Quarterly Report on Form 10-Q for the three months ended March 31, 2019, Anadarko no longer reports an Other Midstream segment and now has two reporting segments as follows:

Exploration and Production—This segment is engaged in the exploration, development, production and sale of oil, natural gas and NGLs and in advancing its Mozambique LNG project toward a final investment decision (FID) in the first half of 2019.

WES Midstream—This segment engages in gathering, processing, treating, and transporting Anadarko and third-party oil, natural gas and NGL production, as well as gathering and disposal of produced water. The WES Midstream segment consists of assets owned by Western Midstream Partners, LP.

Anadarko is incorporated in Delaware. Anadarko’s corporate headquarters is located at 1201 Lake Robbins Drive, The Woodlands, Texas 77380-1046, and its telephone number is (832) 636-1000. Anadarko’s website address is www.anadarko.com. Information contained on Anadarko’s website does not constitute part of this proxy statement/prospectus. Anadarko’s common stock is publicly traded on the NYSE under the ticker symbol APC. Additional information about Anadarko is included in documents incorporated by reference in this proxy statement/prospectus. See Where You Can Find More Information beginning on page 167.

Merger Subsidiary

Merger Subsidiary, an indirect wholly owned subsidiary of Occidental, is a Delaware corporation incorporated on April 5, 2019 for the purpose of effecting the merger. Merger Subsidiary has not conducted any activities other than those incidental to its formation and the matters contemplated by the merger agreement, including the preparation of applicable regulatory filings in connection with the merger. The principal executive offices of Merger Subsidiary are located at 5 Greenway Plaza, Suite 110, Houston, Texas 77046, and its telephone number is (713) 215-7000.

The Merger

On May 9, 2019, Occidental, Merger Subsidiary and Anadarko entered into the merger agreement, which provides that upon the terms and subject to the conditions set forth therein and in accordance with the DGCL, Merger Subsidiary will merge with and into Anadarko, with Anadarko continuing as the surviving corporation and an indirect wholly owned subsidiary of Occidental.

Merger Consideration

In the merger, each share of Anadarko common stock that is issued and outstanding immediately prior to the effective time of the merger (other than (i) cancelled shares, (ii) certain shares of Anadarko common stock subject to stock-based awards that will be treated in the manner described under the heading The Merger—Treatment of Anadarko Stock Options and Other Stock-Based Awards and (iii) dissenting shares (if any)) will be converted into the right to receive the merger consideration, consisting of $59.00 in cash (as such amount of cash may potentially be adjusted pursuant to the merger agreement as described below, the per share cash consideration), without interest, and 0.2934 (as such amount may potentially be adjusted pursuant to the merger agreement as described below, the exchange ratio) of a validly issued, fully paid and non-assessable share of Occidental common stock (such cash consideration and stock consideration together, as they may potentially be adjusted pursuant to the merger agreement as described below, the merger consideration). If the merger would otherwise result in the issuance of shares of Occidental common stock (including shares that would be deliverable pursuant to converted stock-based awards pursuant to the merger agreement) in excess of 19.99% of the outstanding shares of Occidental common stock immediately prior to the closing of the merger (the share cap), (i) the exchange ratio will be reduced by the smallest number (rounded up to the nearest 0.0001) that causes the total number of shares of Occidental common stock (including shares that would be deliverable pursuant to converted stock-based awards pursuant to the merger agreement) issuable in the merger to not exceed the share cap (the exchange ratio reduction number) and (ii) the per share cash consideration will be increased by the amount in cash equal to (x) the exchange ratio reduction number multiplied by (y) the Parent Closing Price.

The exchange ratio is otherwise fixed and will not be adjusted to reflect changes in the stock price of either company prior to the closing of the merger. The exchange ratio will, however, be adjusted appropriately to fully

reflect the effect of any reclassification, recapitalization, stock split or combination, exchange or readjustment of shares, or any stock dividend thereon, with respect to outstanding shares of capital stock of either Occidental or Anadarko with a record date between the date of the merger agreement and the completion of the merger. No fractional shares of Occidental common stock will be issued in connection with the merger. Each holder of Anadarko common stock that otherwise would have been entitled to receive a fractional share of Occidental common stock immediately prior to the effective time of the merger will receive an amount in cash, without interest, rounded to the nearest cent, in lieu of such fractional share. The value of such cash payment will be calculated by the exchange agent and will represent the holders proportionate interest in a trust of proceeds established from the open-market sale of that number of shares of Occidental common stock equal to the excess of (i) the aggregate number of shares of Occidental common stock delivered to the exchange agent by Occidental pursuant to the terms of the merger agreement over (ii) the aggregate number of whole shares of Occidental common stock distributed to the holders of certificates or book-entry shares previously representing shares of Anadarko common stock pursuant to the merger agreement.

Occidental stockholders will continue to own their existing shares of Occidental common stock, the form of which will not be changed by the transaction.

Treatment of Anadarko Stock Options and Other Stock-Based Awards

Anadarko Stock Options. Upon completion of the merger, each outstanding Anadarko stock option will be cancelled and converted into the right to receive a cash amount equal to the product of (i) the excess, if any, of (1) the Option Consideration over (2) the per share exercise price of such Anadarko stock option; and (ii) the aggregate number of shares of Anadarko common stock subject to such Anadarko stock option. Each Anadarko stock option with an exercise price equal to or greater than the Option Consideration will be cancelled and terminated, without any payment in respect thereof.

Anadarko RSU Awards. Upon completion of the merger, each outstanding Anadarko RSU award will convert into an Occidental restricted stock/cash unit award with respect to both (i) the number (rounded to the nearest whole number) of shares of Occidental common stock determined by multiplying (x) the number of shares of Anadarko common stock subject to such Anadarko RSU award by (y) the exchange ratio and (ii) the U.S. dollar amount (rounded to the nearest whole cent) determined by multiplying (1) the number of shares of Anadarko common stock subject to such Anadarko RSU award by (2) the per share cash consideration. Such converted award will otherwise continue on the same terms and conditions as were applicable under such Anadarko RSU award, including any provisions for acceleration of vesting. Such terms and conditions include double-trigger protection of the converted award, meaning that upon certain qualifying terminations of employment during the applicable protection period following the closing of the merger, the award will immediately vest and become unrestricted as of such termination.

Anadarko RS Awards. Upon completion of the merger, each outstanding Anadarko RS award will convert into an Occidental restricted stock/cash award with respect to both (i) the number (rounded to the nearest whole number) of shares of Occidental common stock determined by multiplying (x) the number of shares of Anadarko common stock subject to such Anadarko RS award by (y) the exchange ratio and (ii) the U.S. dollar amount (rounded to the nearest whole cent) determined by multiplying (1) the number of shares of Anadarko common stock subject to such Anadarko RS award by (2) the per share cash consideration. Such converted award will otherwise continue on the same terms and conditions as were applicable under such Anadarko RS award, including any provisions for acceleration of vesting. Such terms and conditions include double-trigger protection of the converted award, meaning that upon certain qualifying terminations of employment during the applicable protection period following the closing of the merger, the award will immediately vest and become unrestricted as of such termination.

Anadarko PU Awards. Upon completion of the merger, each outstanding Anadarko PU award will immediately vest and will be cancelled and converted into the right to receive a cash amount equal to the product of (i) 200% of the target number of shares of Anadarko common stock subject to such Anadarko PU award multiplied by (ii) $76.00, less applicable tax withholdings. This amount will be payable on the earliest date that would not result in the imposition of any tax under Section 409A of the Code.

Anadarko Deferred Share Awards. Upon completion of the merger, each outstanding Anadarko deferred share award will be cancelled and converted into the right to receive the merger consideration in respect of each share of Anadarko common stock subject to such Anadarko deferred share award. This amount will be payable

within five business days following the completion of the merger or, if later, the earliest date that would not result in the imposition of tax under Section 409A of the Code.

For a more complete discussion of the treatment of Anadarko stock options and other Anadarko stock-based awards, see The Merger—Treatment of Anadarko Stock Options and Other Stock-Based Awards beginning on page 91.

Recommendations of the Anadarko Board of Directors

After careful consideration, the Anadarko Board unanimously recommends that holders of Anadarko common stock vote FOR the merger proposal.

After careful consideration, the Anadarko Board unanimously recommends that holders of Anadarko common stock vote FOR the merger-related compensation proposal.

For a more complete description of the Anadarko Board’s reasons for the transaction and the recommendation of the Anadarko Board, see The Merger—Occidental’s Rationale for the Transaction and The Merger—Recommendations of the Anadarko Board of Directors and Its Reasons for the Transaction beginning on pages 54 and 55, respectively.

Opinions of Anadarkos Financial Advisors

Opinion of Evercore Group L.L.C.

Pursuant to an engagement letter dated as of February 15, 2019, Anadarko engaged Evercore Group L.L.C. (Evercore) to act as its financial advisor in connection with a study of potential strategic alternatives available to Anadarko, including a possible sale of Anadarko. As part of this engagement, Anadarko requested that Evercore evaluate the fairness of the merger consideration, from a financial point of view, to the holders of the shares of Anadarko common stock.

At a meeting of the Anadarko Board held on May 9, 2019, Evercore rendered to the Anadarko Board its oral opinion, subsequently confirmed in writing, that as of May 9, 2019 and based upon and subject to the assumptions, limitations, qualifications and conditions described in Evercores written opinion, the merger consideration was fair, from a financial point of view, to the holders of Anadarko common stock entitled to receive such merger consideration.

The full text of the written opinion of Evercore, dated as of May 9, 2019, which sets forth, among other things, the procedures followed, assumptions made, matters considered and qualifications and limitations on the scope of review undertaken in rendering its opinion, is attached as Annex B to this proxy statement/prospectus and is incorporated by reference in its entirety into this proxy statement/prospectus. You are urged to read this opinion carefully and in its entirety. Evercores opinion was addressed to, and provided for the information and benefit of, the Anadarko Board in connection with their evaluation of the merger. The opinion does not constitute a recommendation to the Anadarko Board or to any other person in respect of the merger, including as to how any holder of shares of Anadarko common stock should vote or act in respect of the merger. Evercores opinion does not address the relative merits of the merger as compared to other business or financial strategies that might be available to Anadarko, nor does it address the underlying business decision of Anadarko to engage in the merger.

For further information, see The Merger—Opinions of Anadarko’s Financial Advisors—Opinion of Evercore Group L.L.C. beginning on page 58 and the full text of the written opinion of Evercore attached as Annex B to this proxy statement/prospectus.

Opinion of Goldman Sachs & Co. LLC

At a meeting of the Anadarko Board, Goldman Sachs & Co. LLC (Goldman Sachs) rendered to the Anadarko Board its oral opinion, subsequently confirmed by delivery of a written opinion, dated May 9, 2019, to the Anadarko Board, to the effect that, as of the date of Goldman Sachs written opinion and based upon and subject to the factors and assumptions set forth in Goldman Sachs written opinion, the merger consideration to be paid to the holders (other than Occidental, Berkshire Hathaway and their respective affiliates) of shares of Anadarko common stock pursuant to the merger agreement was fair from a financial point of view to such holders.

The full text of the written opinion of Goldman Sachs, dated May 9, 2019, which sets forth the assumptions made, procedures followed, matters considered, qualifications and limitations on the review undertaken in connection with the opinion, is attached to this proxy statement/prospectus as Annex C. The summary of Goldman Sachs opinion contained in this proxy statement/prospectus is qualified in its entirety by reference to the full text of Goldman Sachs written opinion. Goldman Sachs advisory services and opinion were provided for the information and assistance of the Anadarko Board in connection with its consideration of the merger and the opinion does not constitute a recommendation as to how any Anadarko stockholder should vote with respect to the merger or any other matter.

For more information, see The Merger—Opinions of Anadarko’s Financial Advisors—Opinion of Goldman Sachs & Co. LLC beginning on page 66 and the full text of the written opinion of Goldman Sachs attached as Annex C to this proxy statement/prospectus.

Interests of Directors and Executive Officers of Anadarko in the Merger

You should be aware that some of the directors and executive officers of Anadarko have interests in the merger that are different from, or are in addition to, the interests of stockholders generally. These interests include the following:

•

Executive officers and directors of Anadarko have arrangements with Anadarko that provide for certain benefits upon completion of the merger and/or if their employment or service is terminated under certain circumstances following the completion of the merger, including (i) in the case of executive officers, severance and accelerated vesting of certain equity awards, and (ii) in the case of non-executive directors, distribution of deferred share awards.

•

Executive officers and directors of Anadarko have rights to indemnification, advancement of expenses and directors’ and officers’ liability insurance that will survive the completion of the merger.

The Anadarko Board was aware of these additional interests of their directors and executive officers and considered these potential interests, among other matters, in evaluating and negotiating the merger agreement and the merger, in approving the merger agreement and in recommending the applicable merger-related proposals.

For a further discussion of the interests of Anadarko’s directors and executive officers in the merger, see The Merger—Interests of Directors and Executive Officers of Anadarko in the Merger beginning on page 79.

Material U.S. Federal Income Tax Consequences of the Merger

The merger will be treated as a taxable transaction for U.S. federal income tax purposes. Therefore, a U.S. holder (as defined below in the section entitled The Merger—Material U.S. Federal Income Tax Consequences—General) generally will recognize capital gain or loss equal to the difference between (i) the sum of the cash and the fair market value of any shares of Occidental common stock received by such U.S. holder in the merger and (ii) the U.S. holders adjusted tax basis in its Anadarko common stock.

Except in certain circumstances described in The Merger—Material U.S. Federal Income Tax Consequences—The Merger, a Non-U.S. holder (as defined below in the section entitled The Merger—Material U.S. Federal Income Tax Consequences—General) generally will not be subject to U.S. federal income or withholding tax on any gain recognized on the exchange of Anadarko common stock for any shares of Occidental common stock and cash in the merger.

In certain circumstances, Anadarko stockholders who expect to own an equal or greater percentage interest in Occidental following the merger than their percentage interest in Anadarko prior to the merger, taking into account the application of certain constructive ownership rules, may have tax consequences that differ materially from those described above as a result of the application of Section 304. As described further below under The Merger—Material U.S. Federal Income Tax Consequences—The Merger—Special Consequences of the Merger to Holders of Anadarko Common Stock That Also Own Occidental Common Stock, such stockholders may be required to include the entire amount of the consideration received as dividend income. Non-U.S. holders may be subject to U.S. federal income and withholding tax on such dividend income. In addition, withholding agents may withhold on consideration payable to all Non-U.S. holders because they may not be able to determine whether any particular Non-U.S. holder is subject to withholding as a result of these rules. Any such stockholders who expect to own an equal or greater percentage interest in Occidental following the merger than their

percentage interest in Anadarko prior to the merger and all Non-U.S. holders should consult their own tax advisors regarding the application of Section 304 to the merger.

Please refer to The Merger—Material U.S. Federal Income Tax Consequences—The Merger contained in this proxy statement/prospectus for a description of the material U.S. federal income tax consequences of the merger. Determining the actual tax consequences of the merger to you may be complex and will depend on your specific situation. You are urged to consult your tax advisor for a full understanding of the tax consequences of the merger to you.

Accounting Treatment of the Merger

The merger will be accounted for as an acquisition of Anadarko by Occidental under the acquisition method of accounting in accordance with accounting principles generally accepted in the U.S. (GAAP). For additional information, see The Merger—Accounting Treatment of the Merger beginning on page 88.

Litigation Relating to the Merger

On May 30, 2019, Anadarko received a demand letter from counsel to a purported Anadarko stockholder, seeking inspection of Anadarkos books and records pursuant to Section 220 of the DGCL. On May 9, 2019, Anadarko received a demand letter from counsel to a different purported Anadarko stockholder, seeking inspection of Anadarkos books and records pursuant to Section 220 of the DGCL.

On May 30, 2019, a complaint was filed in the Court of Chancery of the State of Delaware by purported Occidental stockholders High River Limited Partnership, Icahn Partners Master Fund LP and Icahn Partners LP, seeking inspection of Occidentals books and records pursuant to Section 220 of the DGCL. On June 14, 2019, Occidental filed an answer to the complaint in the Court of Chancery of the State of Delaware.

Appraisal Rights

Under Delaware law, if the merger is completed, holders of Anadarko common stock who do not vote in favor of the adoption of the merger agreement and who otherwise comply with the requirements and procedures of Section 262 of the DGCL will be entitled to seek appraisal for, and obtain payment in cash for the judicially determined fair value of, their shares of Anadarko common stock, in lieu of receiving the merger consideration. The fair value could be higher or lower than, or the same as, the merger consideration. A copy of the full text of Section 262 of the DGCL is included as Annex D to this proxy statement/prospectus. Anadarko stockholders are encouraged to read Section 262 of the DGCL carefully and in its entirety. Moreover, due to the complexity of the procedures for exercising the right to seek appraisal, Anadarko stockholders who are considering exercising that right are encouraged to seek the advice of legal counsel. Failure to comply with Section 262 of the DGCL may result in loss of the right of appraisal. For a more detailed description of Anadarko stockholder’s appraisal rights, see The Merger—Appraisal Rights beginning on page 92.

Regulatory Approvals Required for the Merger

The merger is subject to the requirements of the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended (the HSR Act), under which Occidental and Anadarko may not complete the merger until notification and report forms are furnished to the Antitrust Division of the U.S. Department of Justice (DOJ) and the U.S. Federal Trade Commission (FTC) and the HSR Act waiting period is terminated or expires. On May 23, 2019, Occidental and Anadarko each filed their respective requisite notification and report form under the HSR Act with the DOJ and the FTC. The FTC granted early termination of the applicable waiting period under the HSR Act on June 3, 2019.

Conditions to Completion of the Merger

The parties expect to complete the merger after all of the conditions to the merger in the merger agreement are satisfied or waived, including after the merger agreement has been adopted by the stockholders of Anadarko. The parties currently expect to complete the transaction in the second half of 2019. However, it is possible that factors outside of each companys control could require them to complete the transaction at a later time or not to complete it at all.

In addition to the approval of the merger proposal by Anadarko stockholders and the expiration or termination of the applicable waiting period under the HSR Act, each as described above, each partys obligation to complete the merger is also subject to the satisfaction (or, to the extent permitted by law and in accordance with the merger agreement, waiver) of other conditions, including: the effectiveness of the registration statement on Form S-4 of which this proxy statement/prospectus forms a part (and the absence of any stop order by the SEC), approval of the listing on the NYSE of the Occidental common stock to be issued in the merger, the absence of an injunction prohibiting the merger, the accuracy of the representations and warranties of the other party under the merger agreement (subject to the materiality standards set forth in the merger agreement), the performance by the other party of its respective obligations under the merger agreement in all material respects and delivery of an officers certificate by the other party certifying satisfaction of the two preceding conditions.

Neither Occidental nor Anadarko can be certain when, or if, the conditions to the merger will be satisfied or waived, or that the merger will be completed. For a more complete summary of the conditions that must be satisfied or waived prior to completion of the merger, see The Merger Agreement—Conditions to Completion of the Merger beginning on page 120.

Financing of the Merger and Treatment of Existing Debt

Occidentals obligation to close the merger is not conditioned on its ability to obtain financing. Occidental and Merger Subsidiary have represented to Anadarko that proceeds from the debt and equity financing described below, together with cash and marketable securities of Occidental, will be sufficient to enable Occidental to pay at the closing of the merger the cash portion of the merger consideration and to consummate the transactions contemplated by the merger agreement. Occidental estimates that the total amount of cash required to complete the transactions contemplated by the merger, including the cash portion of the merger consideration and payment of fees, expenses and other related amounts incurred in connection with the merger, will be approximately $30.3 billion. Occidental expects to finance the cash portion of the merger consideration and these fees, expenses and amounts with the proceeds of debt and equity financing, including proceeds from the Berkshire Hathaway investment described below.

In connection with its entry into the merger agreement, Occidental entered into a second amended and restated debt commitment letter, dated May 9, 2019 (the debt commitment letter), with Citigroup Global Markets Inc. (CGMI), Bank of America, N.A. (BofA) and Merrill Lynch, Pierce, Fenner & Smith Incorporated (together with its assignee, BofA Securities, Inc., BAML), pursuant to which, subject to the terms and conditions set forth therein, CGMI (on behalf of itself and certain affiliates) and BofA (collectively, the initial bridge commitment parties) committed to provide a 364-day senior unsecured bridge loan facility in an aggregate principal amount of up to $21.8 billion. Such commitments were reduced by an aggregate principal amount of $8.8 billion, to an aggregate principal amount of $13.0 billion, upon Occidentals entry into the term loan credit agreement described below and will be further reduced to the extent that Occidental obtains certain other long-term debt financing or debt financing commitments, completes certain issuances of equity, equity-linked or hybrid debt-equity securities or completes certain asset sales (subject to customary reinvestment rights), including asset sales pursuant to the Total transaction. On June 3, 2019, Occidental and the initial bridge commitment parties entered into a joinder agreement to the debt commitment letter (the bridge joinder agreement), with certain additional commitment parties (the “additional bridge commitment parties”). The bridge joinder agreement amended the debt commitment letter and reallocated the commitments of the initial bridge commitment parties to fund loans under the bridge loan facility among the initial bridge commitment parties and the additional bridge commitment parties (collectively, the bridge commitment parties). The bridge commitment parties obligations to fund the bridge loan facility are subject to several limited conditions as set forth in the debt commitment letter, including, among others, the completion of the merger, the absence of a material adverse effect (as defined in the merger agreement) on Anadarko, the accuracy in all material respects of certain representations and warranties related to Anadarko, as set forth in the merger agreement, and to Occidental, the absence of certain events of default and the delivery of certain financial statements of Occidental and Anadarko.

On June 3, 2019, Occidental entered into an $8.8 billion term loan credit agreement (the term loan credit agreement) with Citibank, N.A., as agent, and certain financial institutions party thereto, as lenders (the term loan lenders), pursuant to which, subject to the terms and conditions set forth therein, the term loan lenders committed to provide (i) a 364-day senior unsecured term loan facility in an aggregate principal amount of up to $4.4 billion and (ii) a two-year senior unsecured term loan facility in an aggregate principal amount of up to

$4.4 billion, for the purposes of financing the merger and paying related fees and expenses. The term loan lenders obligations to fund term loans under the term loan credit agreement are subject to several limited conditions as set forth in the term loan credit agreement, including, among others, the completion of the merger, the absence of a material adverse effect (as defined in the merger agreement) on Anadarko, the accuracy in all material respects of certain representations and warranties related to Anadarko, as set forth in the merger agreement, and to Occidental, the absence of certain events of default and (to the extent also provided to the lead arrangers under the bridge loan facility) the delivery of certain financial statements of Occidental and Anadarko. The term loan credit agreement contains certain customary covenants and events of default, including a customary negative pledge and a covenant that Occidental will maintain, as of the last day of each fiscal quarter, a ratio not in excess of 0.65 to 1.00 of consolidated debt to total capitalization (as such terms are defined in the term loan credit agreement).

On April 30, 2019, Occidental and Berkshire Hathaway Inc. (Berkshire Hathaway) entered into a securities purchase agreement, pursuant to which Berkshire Hathaway agreed to purchase newly issued Occidental preferred stock (the series A preferred stock) and a warrant to purchase Occidental common stock for an aggregate purchase price of $10 billion in cash (the Berkshire Hathaway investment). Berkshire Hathaways purchase of such series A preferred stock and warrant is subject to certain conditions, including completion of the merger.

For more information regarding the financing of the merger, see The Merger—Financing of the Merger and Treatment of Existing Debt beginning on page 89.

Sale of Anadarko Assets to TOTAL S.A.

In connection with the merger, Occidental and TOTAL S.A. (Total) entered into a binding memorandum of understanding, dated May 3, 2019, pursuant to which Occidental has agreed to sell to Total all of the assets, liabilities, businesses and operations of Anadarko in Algeria, Ghana, Mozambique and South Africa for $8.8 billion in cash, on a cash-free, debt-free basis (the Total transaction). The Total transaction is conditioned on the completion of the merger, the execution and delivery of a definitive purchase agreement, and the receipt of required regulatory approvals, as well as other customary closing conditions.

For more information regarding the Total transaction, see The Merger—Sale of Anadarko Assets to TOTAL S.A. beginning on page 91.

No Solicitation

In the merger agreement, Anadarko has agreed that it and its subsidiaries will not, and that it will direct and use its reasonable best efforts to cause its and its subsidiaries respective officers, directors, employees, investment bankers, consultants, attorneys, accountants, agents and other representatives not to, directly or indirectly:

•

take any action to solicit, initiate or knowingly encourage or facilitate the making of any acquisition proposal (as defined on page 109) or any inquiry with respect to an acquisition proposal;

•

engage in discussions or negotiations with any person with respect to an acquisition proposal (except to notify them of the existence of the applicable provisions of the merger agreement);

•

disclose any nonpublic information or afford access to properties, books or records to any person that has made, or to Anadarko’s knowledge is considering making, an acquisition proposal;

•

approve or recommend, propose to approve or recommend, or execute or enter into any agreement relating to an acquisition proposal; or

•

propose publicly or agree to do any of the foregoing.

The merger agreement includes customary exceptions such that, prior to obtaining the Anadarko stockholder approval of the merger proposal (the Anadarko stockholder approval), Anadarko may furnish information and access, and may engage in discussions and negotiations regarding an acquisition proposal, if (i) the Anadarko Board concludes in good faith, after (x) receipt of the advice of a financial advisor of nationally recognized reputation and outside legal counsel, that such acquisition proposal constitutes or could reasonably be expected to result in a superior proposal (as defined on page 110) and (y) taking into account any revised terms proposed by

Occidental after Occidental is notified of such acquisition proposal pursuant to the terms of the merger agreement, that failure to do so would be reasonably likely to be inconsistent with its fiduciary duties to Anadarko’s stockholders under applicable law and (ii) Anadarko receives from the person making such an acquisition proposal an executed confidentiality agreement and complies with certain specified procedures. For a discussion of the limitations on solicitation of acquisition proposals, see The Merger Agreement—Covenants and Agreements—No Solicitation beginning on page 108.

Termination of the Merger Agreement

Termination

The merger agreement may be terminated and the merger may be abandoned at any time prior to the effective time of the merger in any of the following ways:

•

By the mutual written consent of Occidental and Anadarko.

•

By either Occidental or Anadarko:

•

if the merger has not been completed by February 9, 2020 (or, if the reason for not closing by February 9, 2020 is that the regulatory conditions specified in the merger agreement have not been satisfied by that date or because of an injunction prohibiting completion of the merger, and all other closing conditions of the parties have been satisfied, duly waived or are then capable of being satisfied, May 9, 2020) (such date, as it may be extended, the end date), provided that neither Occidental nor Anadarko can terminate the merger agreement due to the occurrence of the end date if its failure to fulfill any obligation under the merger agreement has principally caused or resulted in the failure to complete the merger on or before such end date;

•

if the Anadarko stockholder approval has not been obtained by reason of the failure to obtain the required vote at a duly held meeting of stockholders or at any adjournment thereof;

•

if there is any law or regulation that makes completion of the merger illegal or otherwise prohibited or if any judgment, injunction, order or decree enjoining Occidental or Anadarko from consummating the merger is entered and such judgment, injunction, order or decree becomes final and nonappealable; provided that this right to terminate the merger agreement will not be available to any party whose failure to fulfill any obligation under the covenant to use best efforts has principally caused or resulted in the imposition of such restraint or the failure of such restraint to be resisted, resolved or lifted; or

•

if there has been a breach by the other party of any of its representations, warranties, covenants or agreements contained in the merger agreement, which breach results in the failure to satisfy certain conditions to the obligations of Occidental and Merger Subsidiary (in the case of a breach by Anadarko) or certain conditions to the obligations of Anadarko (in the case of a breach by Occidental) to the merger, and such breach is incapable of being cured or, if capable of being cured, has not been cured within 30 days after written notice thereof to the party alleged to be in breach.

•

By Occidental:

•

prior to receipt of the Anadarko stockholder approval, if there has been a change in the Anadarko recommendation (as defined on page 110), whether or not permitted by the terms of the merger agreement (or the Anadarko Board or any committee thereof resolves to effect a change in the Anadarko recommendation).

•

By Anadarko:

•

in order to enter into a definitive agreement with respect to a superior proposal, only if Anadarko has complied with the specific procedures and requirements set out in the merger agreement with regard to the superior proposal and has paid the applicable termination fee.

If the merger agreement is terminated as described above, the merger agreement will be void and have no effect, and there will be no liability or obligation on the part of any party, except that:

•

certain provisions contained in the merger agreement with respect to the effect of termination, the allocation of costs and expenses and the termination fee will survive the termination of the merger agreement;

•

the agreements contained in the confidentiality agreement between Occidental and Anadarko will survive the termination of the merger agreement; and

•

no termination will relieve any party of any liability or damages resulting from any material and intentional breach by that party of the merger agreement.

In addition, none of the financing sources (as defined on page 121) will have any liability to Anadarko or any of its affiliates, and neither Anadarko nor any of its affiliates will have any rights or claims against any financing sources, relating to or arising out of the merger agreement, the debt commitment letters, the financing for the transactions contemplated by the merger agreement or otherwise.

Termination Fees

The merger agreement further provides that Anadarko will pay or cause to be paid to Occidental a termination fee of $1 billion in connection with a termination of the merger agreement under the following circumstances:

•

if Occidental terminates the merger agreement pursuant to a change in the Anadarko recommendation, then Anadarko will pay or cause to be paid $1 billion not later than the date of termination of the merger agreement;

•

if (i) the merger agreement is terminated by Anadarko or Occidental pursuant to not having obtained the Anadarko stockholder approval by reason of the failure to obtain the required vote at a duly held meeting of stockholders or any adjournment thereof and (ii) on or before the date of such termination an acquisition proposal has been made and become publicly known, whether or not withdrawn, prior to the special meeting, then Anadarko will pay or cause to be paid $1 billion not later than the date an acquisition proposal (defined for this purpose with all references to 20% in the definition of acquisition proposal (found on page 109) being replaced with references to 50%) is consummated or a definitive agreement is entered into by Anadarko providing for any such acquisition proposal, so long as such acquisition proposal is consummated or such definitive agreement is executed within 12 months after the date of termination;

•

if (i) the merger agreement is terminated by Anadarko or Occidental due to the failure to consummate the merger by the end date and the Anadarko stockholder approval has not been obtained and (ii) on or before the date of such termination an acquisition proposal has been made and become publicly known, whether or not withdrawn, prior to the date of such termination, then Anadarko will pay or cause to be paid $1 billion not later than the date an acquisition proposal (defined for this purpose with all references to 20% in the definition of acquisition proposal being replaced with references to 50%) is consummated or a definitive agreement is entered into by Anadarko providing for any such acquisition proposal, so long as such acquisition proposal is consummated or such definitive agreement is executed within 12 months after the date of termination;

•

if (i) the merger agreement is terminated by Occidental pursuant to a breach by Anadarko of any of its representations, warranties, covenants or agreements, which breach resulted in the failure to satisfy one or more of certain additional conditions to the obligations of Occidental and Merger Subsidiary to the merger, and the Anadarko stockholder approval has not been obtained and (ii) on or before the date of such termination an acquisition proposal has been made and become publicly known, whether or not withdrawn, prior to the date of such termination, then Anadarko will pay or cause to be paid $1 billion not later than the date an acquisition proposal (defined for this purpose with all references to 20% in the definition of acquisition proposal being replaced with references to 50%) is consummated or a definitive agreement is entered into by Anadarko providing for any such acquisition proposal, so long as such acquisition proposal is consummated or such definitive agreement is executed within 12 months after the date of termination; or

•

if the merger agreement is terminated by Anadarko pursuant to its entry into a definitive agreement with respect to a superior proposal, then Anadarko will pay or cause to be paid $1 billion not later than the date of termination of the merger agreement.

The merger agreement further provides that Occidental will pay or cause to be paid to Anadarko a termination fee of $1 billion if the merger agreement is terminated by Anadarko pursuant to a breach by Occidental of any of its representations, warranties, covenants or agreements, which breach resulted in the failure to satisfy certain conditions to the obligations of Anadarko to the merger. In such circumstances, Occidental will pay or cause to be paid $1 billion within two business days after the date of termination of the merger agreement.

For a more detailed discussion of each party’s termination rights and the related termination fee obligations, see The Merger Agreement—Termination of the Merger Agreement beginning on page 120.

Special Meeting

Date, Time, Place and Purpose

The special meeting will be held on August 8, 2019, at 8:00 a.m., local time, at The Westin at The Woodlands, 2 Waterway Square Place, The Woodlands, Texas, 77380. At the special meeting, Anadarko stockholders will be asked to consider and vote on the merger proposal and the merger-related compensation proposal. Completion of the merger is conditioned on the approval of the merger proposal.

Record Date; Stockholders Entitled to Vote

Only holders of record of Anadarko common stock at the close of business on July 11, 2019, the record date, will be entitled to notice of, and to vote at, the special meeting or any adjournment or postponement thereof.

At the close of business on July 8, 2019, the most recent practicable date for which such information was available, there were 502,401,622 shares of Anadarko common stock outstanding and entitled to vote at the special meeting. The number of shares of Anadarko common stock outstanding and entitled to vote at the special meeting as of the record date is not expected to be meaningfully different from the number as of July 8, 2019. Each share of Anadarko common stock outstanding on the record date entitles the holder thereof to one vote on each proposal to be considered at the special meeting. Anadarko stockholders may vote in person or by proxy through the internet or by telephone or by a properly executed and delivered proxy card with respect to the special meeting.

A complete list of stockholders entitled to vote at the special meeting will be available for viewing by any Anadarko stockholder during ordinary business hours for a period of ten days before the meeting, for purposes pertaining to the special meeting, at Anadarkos offices at 1201 Lake Robbins Drive, The Woodlands, Texas 77380, and at the time and place of the special meeting during the full duration of the meeting.

Quorum; Abstentions and Broker Non-Votes

A quorum of Anadarko stockholders is necessary for Anadarko to hold the special meeting. The holders of a majority of the outstanding shares of Anadarko common stock entitled to vote at the special meeting must be present in person or represented by proxy in order to constitute a quorum.

If you submit a properly executed proxy card, even if you do not vote for the proposal or vote to abstain in respect of the proposal, your shares of Anadarko common stock will be counted for purposes of calculating whether a quorum is present for the transaction of business at the special meeting. Anadarko common stock held in street name with respect to which the beneficial owner fails to give voting instructions to the broker, bank or other nominee, and Anadarko common stock with respect to which the beneficial owner otherwise fails to vote, will not be considered present at the special meeting for the purpose of determining the presence of a quorum.

A broker non-vote occurs when a broker, bank or other nominee holding shares for a beneficial owner has not received voting instructions from the beneficial owner and the broker, bank or other nominee does not have discretionary authority to vote the shares. If you hold your shares of Anadarko common stock in street name and do not provide voting instructions to your broker, bank or other nominee, your shares will be considered to be broker non-votes and will not be considered to be present at the special meeting for the purpose of determining the presence of a quorum.

Approval of the merger proposal requires the affirmative vote of holders of a majority of the outstanding shares of Anadarko common stock entitled to vote thereon. Failures to vote, broker non-votes and abstentions will have the same effect as a vote cast AGAINST the merger proposal.

Required Vote to Approve the Merger-Related Compensation Proposal

Approval of the merger-related compensation proposal requires the affirmative vote of holders of a majority of the outstanding shares of Anadarko common stock present in person or represented by proxy at the special meeting and entitled to vote thereon. Failures to vote and broker non-votes will have no effect on the vote for this proposal (assuming a quorum is present); abstentions will have the same effect as a vote cast AGAINST the approval of this proposal.

Voting by Anadarkos Directors and Executive Officers

At the close of business on July 8, 2019, the most recent practicable date for which such information was available, directors and executive officers of Anadarko and their respective affiliates owned and were entitled to vote 1,163,013 shares of Anadarko common stock, representing less than 1% of the shares of Anadarko common stock outstanding on that date. The number and percentage of shares of Anadarko common stock owned by directors and executive officers of Anadarko and their respective affiliates as of the record date are not expected to be meaningfully different from the number and percentage as of July 8, 2019. Anadarko currently expects its directors and executive officers to vote their shares of Anadarko common stock in favor of each of the proposals to be voted on at the special meeting, but no director or executive officer has entered into any agreement obligating him or her to do so.

Risk Factors

You should consider all the information contained in, and incorporated by reference into, this proxy statement/prospectus in deciding how to vote for the proposals presented in the proxy statement/prospectus. In particular, you should consider the factors described under Risk Factors beginning on page 32.

The following selected historical financial information is being provided to assist you in your analysis of the financial aspects of the transaction.

The Occidental annual historical information is derived from the audited consolidated financial statements of Occidental as of and for each of the years in the five-year period ended December 31, 2018. The Occidental data as of and for the three months ended March 31, 2019 and 2018 has been derived from the unaudited interim financial statements of Occidental and, in the opinion of Occidentals management, includes all normal and recurring adjustments that are considered necessary for the fair presentation of the results for those interim periods.

The Anadarko annual historical information is derived from the audited consolidated financial statements of Anadarko as of and for each of the years in the five-year period ended December 31, 2018. The Anadarko data as of and for the three months ended March 31, 2019 and 2018 has been derived from the unaudited interim financial statements of Anadarko and, in the opinion of Anadarkos management, includes all normal and recurring adjustments that are considered necessary for the fair presentation of the results for those interim periods.

The information is only a summary and should be read in conjunction with each company’s historical consolidated financial statements and related notes contained in Occidental’s and Anadarko’s respective Annual Reports on Form 10-K for the year ended December 31, 2018 and Quarterly Reports on Form 10-Q for the quarter ended March 31, 2019, which are incorporated by reference into this proxy statement/prospectus, as well as other information that has been filed with the SEC, including the Form 8-K which Anadarko filed on May 15, 2019 in order to recast the segment information included in Anadarko’s Annual Report on Form 10-K for the year ended December 31, 2018, following a change in its reportable segments during the quarter ended March 31, 2019. For information on where you can obtain copies of this information, see Where You Can Find More Information beginning on page 167. The historical results included below and elsewhere in this proxy statement/prospectus or incorporated by reference herein are not necessarily indicative of the future performance of Occidental, Anadarko or the combined company after the transaction.

Consolidated for Occidental and its subsidiaries. The statements of income and cash flows related to California Resources have been treated as discontinued operations for all periods presented. The assets and liabilities of California Resources were removed from Occidental’s consolidated balance sheet as of November 30, 2014.

(2)

See the MD&A of Occidental’s Annual Report on Form 10-K for the year ended December 31, 2018 and the Notes to the Consolidated Financial Statements contained therein for information regarding acquisitions and dispositions, discontinued operations and other items affecting comparability.

(3)

Market capitalization is calculated by multiplying the year-end total shares of common stock outstanding, net of shares held as treasury stock, by the year-end closing stock price.

The selected unaudited pro forma condensed combined financial statements (the selected pro forma financial statements) presented below have been prepared from the respective historical consolidated financial statements of Occidental and Anadarko and have been adjusted to reflect (i) the completion of the merger, (ii) Occidentals incurrence of $21.8 billion of new indebtedness to finance a portion of the cash merger consideration, (iii) the Berkshire Hathaway investment (but excluding the exercise of the warrant issued pursuant to the Berkshire Hathaway investment) and (iv) the Total transaction (collectively, the transactions). The selected pro forma financial statements have been prepared as if those transactions had been completed on January 1, 2018, for statement of income purposes, and on March 31, 2019, for balance sheet purposes. The selected pro forma financial statements do not include the realization of cost savings from operating efficiencies, revenue synergies or other integration costs expected to result from the merger.

The selected pro forma financial statements, which are preliminary in nature, have been prepared from, and should be read in conjunction with, (i) the more detailed unaudited pro forma combined financial information and the related notes appearing in the section entitled Unaudited Pro Forma Condensed Combined Financial Data beginning on page 132 and (ii) the separate historical consolidated financial statements and related notes of each of Occidental and Anadarko included elsewhere in this proxy statement/prospectus and incorporated by reference herein (see Where You Can Find More Information beginning on page 167).

The selected pro forma financial statements are provided for illustrative purposes only and do not purport to represent what the actual consolidated results of operations or consolidated financial position of Occidental would have been had the transactions occurred on the dates assumed, nor are they necessarily indicative of future consolidated results of operations or consolidated financial position.

The following table sets forth selected historical per share information of Occidental and Anadarko and unaudited pro forma combined consolidated per share information reflecting the transaction between Occidental and Anadarko, under the acquisition method of accounting, including the issuance of 0.2934 of a validly issued, fully paid and non-assessable share of Occidental common stock in exchange for each share of Anadarko common stock. You should read this information in conjunction with (i) the selected historical financial information and the related notes included elsewhere in this proxy statement/prospectus, (ii) the historical financial statements of Occidental and Anadarko and related notes contained in Occidental’s and Anadarko’s respective Annual Reports on Form 10-K for the year ended December 31, 2018 and Quarterly Reports on Form 10-Q for the quarter ended March 31, 2019, which are incorporated by reference into this proxy statement/prospectus, and (iii) the financial information contained in the Unaudited Pro Forma Condensed Combined Financial Data and the related notes thereto beginning on page 132. The historical per share information is derived from audited financial statements of each of Occidental and Anadarko as of and for the year ended December 31, 2018 and their respective unaudited financial statements for the three months ended March 31, 2019.

The unaudited pro forma combined consolidated per share information has been presented for illustrative purposes only and is based on assumptions and estimates considered appropriate by Occidentals management. The pro forma data presented does not represent what the actual results of operations and financial position would have been had the companies actually been combined as of the beginning of the periods presented and is not necessarily indicative of the future consolidated results of operations or financial position of the combined company. For example, the unaudited pro forma combined consolidated per share information does not reflect cost savings or other future financial impacts that may result from the transaction.

Occidental and Anadarko declared and paid dividends during the periods presented. For more information on dividends of Occidental and Anadarko, see Comparative Per Share Market Price and Dividend Information beginning on page 27.

As of/Forthe ThreeMonthsEndedMarch 31,2019

As of/Forthe YearEndedDecember 31,2018

Occidental Historical per Common Share Data:

Net income-basic

$

0.84

$

5.40

Net income-diluted

$

0.84

$

5.39

Book value(1)

$

28.39

$

28.48

Anadarko Historical per Common Share Data:

Net income-basic

$

(0.03

)

$

1.20

Net income-diluted

$

(0.03

)

$

1.20

Book value(1)

$

18.22

$

17.34

Unaudited Pro Forma Combined per Occidental Common Share Data:

Net income-basic

$

0.14

$

3.09

Net income-diluted

$

0.14

$

3.04

Book value(2)

$

42.14

N/A

Unaudited Pro Forma Combined per Anadarko Equivalent Share Data:

Net income-basic(3)

$

0.04

$

0.91

Net income-diluted(3)

$

0.04

$

0.89

Book value(2)(3)

$

12.36

N/A

(1)

Amount is calculated by dividing stockholders’ equity by the number of common shares outstanding as of the end of the applicable period.

(2)

Amount is calculated by dividing pro forma stockholders’ equity as of March 31, 2019 by the pro forma number of common shares outstanding as of May 2, 2019. Pro forma book value per share as of December 31, 2018, is not meaningful as the estimated pro forma adjustments were calculated as of March 31, 2019.

(3)

Amounts calculated by multiplying unaudited pro forma combined per share amounts by the exchange ratio in the merger of 0.2934 of a share of Occidental common stock for each share of Anadarko common stock.

On April 11, 2019, the last trading day before Anadarko announced it had entered into a merger agreement with Chevron Corporation, which merger agreement was subsequently terminated by Anadarko, the closing sale price per share of Occidental common stock was $67.18 and the closing sale price per share of Anadarko common stock was $46.80, in each case on the NYSE. On May 3, 2019, the last trading day before the public announcement of Occidentals final proposal to acquire Anadarko, the closing sale price per share of Occidental common stock was $57.95 and the closing sale price per share of Anadarko common stock was $72.72, in each case on the NYSE. On May 8, 2019, the last trading day before the public announcement of the merger, the closing sale price per share of Occidental common stock was $60.21 and the closing sale price per share of Anadarko common stock was $75.86, in each case on the NYSE. On July 8, 2019, the latest practicable date before the date of this proxy statement/prospectus, the closing sale price per share of Occidental common stock was $49.30 and the closing sale price per share of Anadarko common stock was $70.91, in each case on the NYSE. The table below sets forth the equivalent market value per share of Anadarko common stock on April 11, 2019, May 3, 2019, May 8, 2019 and July 8, 2019, as determined by multiplying the closing prices of shares of Occidental common stock on those dates by the exchange ratio of 0.2934 and adding the cash portion of the merger consideration of $59.00 per share, without interest.

OccidentalCommon Stock

AnadarkoCommon Stock

Implied Per ShareValue of MergerConsideration

April 11, 2019

$

67.18

$

46.80

$

78.71

May 3, 2019

$

57.95

$

72.72

$

76.00

May 8, 2019

$

60.21

$

75.86

$

76.67

July 8, 2019

$

49.30

$

70.91

$

73.46

The market prices of Occidental common stock and Anadarko common stock have fluctuated since the dates set forth above and will continue to fluctuate from the date of this proxy statement/prospectus to the date of the special meeting and the date the merger is completed and thereafter. No assurance can be given concerning the market prices of Occidental common stock or Anadarko common stock before completion of the merger or Occidental common stock after completion of the merger. The exchange ratio is fixed (except for adjustments in limited circumstances pursuant to the merger agreement as described in the The Merger Agreement—Merger Consideration—Share Cap Adjustment beginning on page 102) and will not be adjusted to reflect changes in the stock price of either company prior to the closing of the merger, but the market price of Occidental common stock (and therefore the value of the merger consideration) when received by Anadarko stockholders after the merger is completed will depend on the closing price of Occidental common stock on the day such stockholders receive their shares of Occidental common stock pursuant to the merger agreement. Such market price could be greater than, less than or the same as shown in the table above. Accordingly, Anadarko stockholders are advised to obtain current market quotations for Occidental common stock and Anadarko common stock in deciding whether to vote for adoption of the merger agreement.

Dividends

Occidental currently pays a quarterly dividend on shares of Occidental common stock and last paid a dividend on April 15, 2019 of $0.78 per share. On May 9, 2019, Occidental announced a dividend of $0.78 per share, to be paid on July 15, 2019 to Occidental stockholders of record as of June 10, 2019. On July 11, 2019, Occidental announced a dividend of $0.79 per share, to be paid on October 15, 2019 to Occidental stockholders of record as of September 10, 2019. Under the terms of the merger agreement, during the period before completion of the merger, Occidental is not permitted to declare, set aside or pay any dividend or other distribution other than its regular cash dividend in the ordinary course of business consistent with past practice, including increases in such dividends consistent with past practice, and in any event will not include any special dividend.

Anadarko currently pays a quarterly dividend on shares of Anadarko common stock and last paid a dividend on March 27, 2019 of $0.30 per share to stockholders of record at the close of business on March 13, 2019. On May 15, 2019, Anadarko announced a dividend of $0.30 per share, which was paid on June 26, 2019 to

Anadarko stockholders of record as of June 12, 2019. Under the terms of the merger agreement, during the period before completion of the merger, Anadarko is not permitted to declare, set aside or pay any dividend or other distribution other than its regular cash dividend in the ordinary course of business consistent with past practice, which, (i) in the case of Anadarko, will not exceed $0.30 per share of Anadarko common stock per fiscal quarter and (ii) in the case of Western Midstream Partners, LP, may include increases to the extent consistent with financial guidance published prior to the date of the merger agreement, and in any case will not include any special dividend.

Furthermore, under the merger agreement, Occidental and Anadarko have agreed to coordinate with each other regarding the declaration and payment of dividends in respect of their common stock and the record dates and payment dates relating thereto, so as to ensure that Anadarko stockholders do not receive two dividends, or fail to receive one dividend, in any quarter with respect to shares of Anadarko common stock and the Occidental common stock that such holders receive in exchange therefor in the merger. Anadarko will ensure that the date on which any quarterly dividend is declared and the record date with respect to any quarterly dividend will be no later than five business days following the one-year anniversary of such dates for the corresponding quarter of the preceding year. In the quarter in which the closing of the merger occurs, if the record date of Occidentals quarterly dividend has been declared and is a date prior to the effective time of the merger, then the quarterly dividend declaration date and record date of Anadarko must occur no later than such date as is necessary to ensure that holders of Anadarko common stock receive a quarterly dividend in accordance with the first sentence of this paragraph.

After completion of the merger, each former Anadarko stockholder who holds shares of Occidental common stock into which shares of Anadarko common stock have been converted in connection with the merger will receive all dividends or other distributions declared and paid on shares of Occidental common stock with a record date on or after the completion of the merger. However, no dividend or other distribution having a record date after completion of the merger will actually be paid with respect to any shares of Occidental common stock into which shares of Anadarko common stock have been converted in connection with the merger until the certificates formerly representing shares of Anadarko common stock have been surrendered or the book-entry shares formerly representing shares of Anadarko common stock have been transferred to the exchange agent in accordance with the merger agreement, at which time any such accrued dividends and other distributions on those shares of Occidental common stock will be paid without interest. Subject to the limitations set forth in the merger agreement described above, any future dividends by Occidental will be made at the discretion of the Occidental Board. Subject to the limitations set forth in the merger agreement described above, any future dividends by Anadarko will be made at the discretion of the Anadarko Board. There can be no assurance that any future dividends will be declared or paid by Occidental or Anadarko or as to the amount or timing of those dividends, if any.

For more details regarding dividends, see The Merger Agreement—Covenants and Agreements—Conduct of Business—Coordination of Dividends beginning on page 114.

This document contains certain forward-looking statements with respect to the financial condition, results of operations and business of Occidental and Anadarko, the combined businesses of Occidental and Anadarko and certain plans and objectives of Occidental and Anadarko with respect thereto, including statements about the merger and the Total transaction and the expected benefits of the transactions. These statements may be made directly in this proxy statement/prospectus or may be incorporated by reference to other documents and may include statements for the period after completion of the merger. These forward-looking statements can be identified by the fact that they do not relate only to historical or current facts. Forward-looking statements often use words such as anticipate, target, expect, estimate, intend, plan, goal, believe, hope, aim, continue, will, may, would, could or should or other words of similar meaning. There are several factors which could cause actual plans and results to differ materially from those expressed or implied in forward-looking statements. Such factors include, but are not limited to, the following:

•

the ability of Occidental and Anadarko to consummate the merger, including the ability to receive the required regulatory approvals (and the risk that such approvals may result in the imposition of conditions that could adversely affect the combined company or the expected benefits of the merger) and approval by the Anadarko stockholders and to satisfy the other conditions to the closing of the merger on a timely basis or at all;

•

the occurrence of events that may give rise to a right of one or both of the parties to terminate the merger agreement, including under circumstances that might require Anadarko to pay or cause to be paid a termination fee of $1 billion to Occidental or under circumstances that might require Occidental to pay or cause to be paid a termination fee of $1 billion to Anadarko;

•

the possibility that the merger is delayed or does not occur;

•

Occidental’s ability to finance the merger, including completion of any contemplated debt financing or equity investment;

•

the possibility that the anticipated benefits from the merger cannot be realized in full or at all or may take longer to realize than expected, including risks associated with achieving expected synergies, cost savings, capital spending reductions and operating efficiencies from the merger;

•

negative effects of the announcement of Occidental’s proposal to acquire Anadarko or the announcement or completion of the merger on the market price of Occidental’s and/or Anadarko’s common stock, their respective financial performance and their respective ability to maintain relationships with suppliers and customers;

•

the risks related to Anadarko and Occidental being restricted in the operation of their respective businesses while the merger agreement is in effect;

•

risks relating to the value of Occidental’s shares to be issued in the merger, significant merger costs and/or unknown liabilities;

•

risks associated with third-party contracts containing change in control consent requirements and/or other provisions that may be triggered by the merger or the transactions;

the ability of Occidental and Anadarko, or the combined company, to retain and hire key personnel;

•

future levels of capital spending;

•

Occidental’s indebtedness and other payment obligations, including the substantial indebtedness Occidental expects to incur in connection with the merger and the need to generate sufficient cash flows to service and repay such debt and to pay dividends on the series A preferred stock to be issued pursuant to the Berkshire Hathaway investment;

•

Occidental’s ability to consummate the Total transaction, including the ability to receive the required regulatory approvals;

the timing and scope of future repurchases of Occidental’s common stock, which may be suspended at any time due to a variety of factors, including the market price of Occidental’s shares, general market conditions, transaction-related restrictions, failure to pay dividends on or make required redemptions of the series A preferred stock and the level of other investing activities and uses of cash, including in connection with the merger;

•

changing crude oil, natural gas and NGL prices;

•

changing marketing and chemicals margins;

•

actions of competitors or regulators;

•

advances in the competitiveness of alternate-energy sources or product substitutes;

•

the timing of exploration expenses and crude oil liftings;

•

technological developments;

•

the results of operations and financial condition of the suppliers, vendors, partners and equity affiliates of Occidental, Anadarko or the combined company, particularly during extended periods of low prices for crude oil and natural gas;

•

the inability or failure of Occidental’s, Anadarko’s or the combined company’s joint-venture partners to fund their share of operations and development activities;

•

the potential failure to achieve expected net production from existing and future crude oil and natural gas development projects;

•

potential delays in the development, construction or start-up of planned projects;

•

the potential disruption or interruption of the operations of Occidental, Anadarko or the combined company due to natural or human causes beyond such company’s control, including crude oil production quotas or other actions that might be imposed by the Organization of Petroleum Exporting Countries;

•

changing economic, regulatory and political environments in the various countries in which Occidental, Anadarko or the combined company operates;

•

the potential liability for remedial actions or assessments under existing or future environmental regulations and litigation;

government-mandated sales, divestitures, recapitalizations, industry-specific taxes, tariffs, sanctions, changes in fiscal terms or restrictions on the scope of company operations;

•

foreign currency movements compared with the U.S. dollar; and

•

other risk factors as detailed from time to time in Occidental’s and Anadarko’s reports filed with the SEC, including Occidental’s and Anadarko’s respective Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K and other documents filed with the SEC, including the risks and uncertainties set forth in, or incorporated by reference into, this proxy statement/prospectus in the section entitled Risk Factors beginning on page 32. See Where You Can Find More Information beginning on page 167.

These forward-looking statements reflect Occidentals and Anadarkos current views with respect to future events and are based on numerous assumptions and assessments made by Occidental and Anadarko in light of their experience and perception of historical trends, current conditions, business strategies, operating environments, future developments and other factors they believe appropriate. By their nature, forward-looking statements involve known and unknown risks and uncertainties because they relate to events and depend on circumstances that will occur in the future. The factors described in the context of such forward-looking statements in this document could cause Occidentals and Anadarkos plans with respect to the merger, actual

results, performance or achievements, industry results and developments to differ materially from those expressed in or implied by such forward-looking statements. Although it is believed that the expectations reflected in such forward-looking statements are reasonable, no assurance can be given that such expectations will prove to have been correct and persons reading this document are therefore cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date of this proxy statement/prospectus or, in the case of a document incorporated by reference, as of the date of that document. Neither Occidental nor Anadarko assumes any obligation to update the information contained in this document (whether as a result of new information, future events or otherwise), except as required by applicable law.

In addition to the other information included in and incorporated by reference into this proxy statement/prospectus, including the matters addressed in Cautionary Note Regarding Forward-Looking Statements beginning on page 29, Anadarko stockholders should carefully consider the following risk factors before deciding whether to vote for the proposal to adopt the merger agreement. In addition, you should read and consider the risks associated with each of the businesses of Anadarko and Occidental because these risks will relate to the combined company following the completion of the merger. Descriptions of some of these risks can be found in the respective Annual Reports of Occidental and Anadarko on Form 10-K for the fiscal year ended December 31, 2018, as such risks may be updated or supplemented in each company’s subsequently filed Quarterly Reports on Form 10-Q or Current Reports on Form 8-K, which are incorporated by reference into this proxy statement/prospectus. You should also consider the other information in this document and the other documents incorporated by reference into this document. See Where You Can Find More Information beginning on page 167.

Risks Related to the Merger

The merger is subject to conditions, some or all of which may not be satisfied or completed on a timely basis, if at all. Failure to complete the merger in a timely manner or at all could have material adverse effects on Occidental and Anadarko.

The completion of the merger is subject to a number of conditions, including, among others, (i) the adoption by Anadarko stockholders of the merger agreement, (ii) the termination or expiration of the waiting period under the HSR Act and (iii) the absence of an injunction prohibiting completion of the merger, which make the completion and timing of the completion of the merger uncertain. For a more detailed discussion regarding conditions to the merger, see The Merger Agreement—Conditions to Completion of the Merger beginning on page 120. Also, either Occidental or Anadarko may terminate the merger agreement if the merger has not been consummated by February 9, 2020 (or, if the reason for not closing by February 9, 2020 is that the regulatory conditions specified in the merger agreement have not been satisfied by that date or because of an injunction prohibiting completion of the merger, and all other closing conditions of the parties have been satisfied, duly waived or are then capable of being satisfied, May 9, 2020), except that this right to terminate the merger agreement due to the occurrence of the end date will not be available to any party whose failure to perform any obligation under the merger agreement has principally caused or resulted in the failure of the merger to be consummated on or before that date.

If the merger is not completed, Occidentals and Anadarkos respective ongoing businesses, financial condition, financial results and stock prices may be materially adversely affected and, without realizing any of the benefits of having completed the merger, Occidental and Anadarko will be subject to a number of risks, including the following:

•

the market price of Occidental common stock or Anadarko common stock could decline to the extent that the current market price reflects a market assumption that the transaction will be completed;

•

each party could owe substantial termination fees to the other party under certain circumstances (see The Merger Agreement—Termination of the Merger Agreement beginning on page 120);

•

if the merger agreement is terminated and the Occidental Board or the Anadarko Board seeks another business combination, Occidental stockholders and Anadarko stockholders cannot be certain that Occidental or Anadarko will be able to find a party willing to enter into a transaction on terms equivalent to or more attractive than the terms that the other party has agreed to in the merger agreement;

•

time and resources committed by Occidental’s and Anadarko’s respective management to matters relating to the merger could otherwise have been devoted to pursuing other beneficial opportunities for their respective companies;

•

Occidental or Anadarko may experience negative reactions from the financial markets or from their respective customers, suppliers or employees; and

•

Occidental and Anadarko will be required to pay their respective costs relating to the merger, such as legal, accounting, financial advisory and printing fees, whether or not the merger is completed.

In addition, if the merger is not completed, Occidental or Anadarko could be subject to litigation related to any failure to complete the merger or related to any enforcement proceeding commenced against Occidental or Anadarko to perform their respective obligations under the merger agreement. The materialization of any of these risks could adversely impact Occidental and Anadarkos respective ongoing businesses, financial condition, financial results and stock price.

Similarly, delays in the completion of the merger could, among other things, result in additional transaction costs, loss of revenue or other negative effects associated with uncertainty about completion of the merger.

The merger is subject to the requirements of the HSR Act, and regulatory authorities may impose conditions that could have an adverse effect on Anadarko, Occidental or the combined company or that could delay, prevent or increase the costs associated with completion of the merger.

Before the merger may be completed, any waiting period (or extension thereof) applicable to the merger under the HSR Act must have expired or been terminated. On May 23, 2019, Occidental and Anadarko each filed their respective requisite notification and report form under the HSR Act with the DOJ and the FTC. The FTC granted early termination of the applicable waiting period under the HSR Act on June 3, 2019. Occidental and Anadarko are not currently aware of any material governmental consents, approvals or filings that are required prior to the parties completion of the transaction other than those under the HSR Act. If additional approvals, consents, clearances or filings are required to complete the transaction, Occidental and Anadarko intend to seek such consents and approvals and make such filings. Regulators may impose conditions, terms, obligations or restrictions in connection with granting approvals or consents for the merger, and such conditions, terms, obligations or restrictions may delay completion of the merger or impose additional material costs on or materially limit the revenues of the combined company following the completion of the merger. There can be no assurance that regulators will choose not to impose such conditions, terms, obligations or restrictions, and, if imposed, such conditions, terms, obligations or restrictions may delay or lead to the abandonment of the merger.

Under the merger agreement, Occidental and Anadarko have agreed to use their respective best efforts to obtain as soon as practicable all approvals, consents, registrations, permits, authorizations and other confirmations required to be obtained from any third party or governmental body, agency, authority or official which are necessary, proper or advisable to consummate the merger, except that Occidental may not be required to undertake, or to request or authorize Anadarko to undertake, any efforts or to take any action if such efforts or action would, or would reasonably be expected to, result in changes or effects which would, individually or in the aggregate, result in, or be reasonably likely to result in, a substantial detriment. As used in this proxy statement/prospectus substantial detriment means changes or effects which would, individually or in the aggregate (and after giving effect to any reasonably expected proceeds of any divestiture or sale of assets), result in, or be reasonably likely to result in, a material adverse effect on Anadarko and its subsidiaries, taken as a whole, at or after the effective time of the merger. Any requirement to divest, hold separate or limit the operation of any division, subsidiary, interest, business, product line, asset or property relating to the operations conducted by Occidental and its subsidiaries prior to the effective time of the merger will be deemed to result in a substantial detriment if such action with respect to a comparable amount of assets or businesses of Anadarko and its subsidiaries, taken together with all other such actions taken, would be reasonably likely, in the aggregate, to have a material adverse effect on Anadarko and its subsidiaries, taken as a whole, at or after the effective time of the merger.

For a more detailed description of the regulatory review process under the HSR Act, see The Merger—Regulatory Approvals Required for the Merger beginning on page 88.

The exchange ratio is fixed (except for adjustments in limited circumstances pursuant to the merger agreement) and will not be adjusted in the event of any change in either Occidentals or Anadarkos stock price. As a result, the stock portion of the merger consideration payable to Anadarkos stockholders may be subject to change if Occidentals stock price fluctuates.

Upon completion of the merger, each share of Anadarko common stock will be converted into the right to receive $59.00 in cash and 0.2934 of a validly issued, fully paid and non-assessable share of Occidental common stock, subject to adjustment only in the event that the merger would otherwise result in the issuance of shares of Occidental common stock (including shares that would be deliverable pursuant to converted stock-based awards pursuant to the merger agreement) in excess of 19.99% of the outstanding shares of Occidental common stock immediately prior to the closing of the merger. See The Merger Agreement—Merger Consideration beginning

on page 102. The exchange ratio will not be adjusted for changes in the market price of either Occidental common stock or Anadarko common stock between the date the merger agreement was signed and completion of the merger. Due to the fixed exchange ratio, fluctuations in the price of Occidental common stock will drive corresponding changes in the value of the stock portion of the merger consideration payable to each Anadarko stockholder. As a result, changes in the price of Occidental common stock prior to the completion of the merger will affect the value of Occidental common stock that Anadarko common stockholders will receive pursuant to the merger.

The price of Occidental common stock has fluctuated during the period between the date the merger agreement was executed and the date of this proxy statement/prospectus, and may continue to change through the date of the special meeting and the date the merger is completed. For example, based on the range of closing prices of Occidental common stock during the period from April 11, 2019, the last trading day before Anadarko announced it had entered into a merger agreement with Chevron Corporation, which merger agreement was subsequently terminated by Anadarko, through July 8, 2019, the latest practicable trading date before the date of this proxy statement/prospectus, the exchange ratio represented a value of the stock portion of the merger consideration ranging from a high of $19.71 to a low of $13.92 for each share of Anadarko common stock. The actual market value of the Occidental common stock received by holders of Anadarko common stock upon completion of the merger may be outside this range.

These variations could result from changes in the business, operations or prospects of Occidental or Anadarko prior to or following the completion of the merger, regulatory considerations, general market and economic conditions and other factors both within and beyond the control of Occidental or Anadarko. At the time of the special meeting, Anadarko stockholders will not know with certainty the value of the shares of Occidental common stock that they will receive upon completion of the merger.

The merger agreement contains provisions that limit Anadarkos ability to pursue alternatives to the merger, could discourage a potential competing acquiror of Anadarko from making a favorable alternative transaction proposal and, in specified circumstances, could require Anadarko to pay a substantial termination fee to Occidental.

The merger agreement contains certain provisions that restrict Anadarkos ability to initiate, solicit, knowingly encourage or facilitate or, subject to certain exceptions, engage in discussions or negotiations with respect to, or approve or recommend, any third-party proposal for an alternative transaction. Further, even if the Anadarko Board withdraws or qualifies its recommendation with respect to the adoption of the merger agreement, unless the merger agreement has been terminated in accordance with its terms, Anadarko will still be required to submit each of its merger-related proposals to a vote at the special meeting. In addition, Occidental generally has an opportunity to offer to modify the terms of the transactions contemplated by the merger agreement in response to any third-party alternative transaction proposal before the Anadarko Board may withdraw or qualify its recommendation with respect to the merger-related proposals or otherwise terminate the merger agreement.

In some circumstances, upon termination of the merger agreement, Anadarko will be required to pay a termination fee of $1 billion to Occidental. See The Merger Agreement—Covenants and Agreements—No Solicitation beginning on page 108 and The Merger Agreement—Termination of the Merger Agreement beginning on page 120.